Common Weakness Enumeration

CWE-770

Allowed

Allocation of Resources Without Limits or Throttling

Abstraction: Base · Status: Incomplete

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

3084 vulnerabilities reference this CWE, most recent first.

GHSA-G7F3-828F-7H7M

Vulnerability from github – Published: 2025-10-10 22:54 – Updated: 2025-11-03 18:31

Summary

Authlib : JWE zip=DEF decompression bomb enables DoS

Details

Summary

Authlib’s JWE zip=DEF path performs unbounded DEFLATE decompression. A very small ciphertext can expand into tens or hundreds of megabytes on decrypt, allowing an attacker who can supply decryptable tokens to exhaust memory and CPU and cause denial of service.

Details

Affected component: Authlib JOSE, JWE zip=DEF (DEFLATE) support.
In authlib/authlib/jose/rfc7518/jwe_zips.py, DeflateZipAlgorithm.decompress calls zlib.decompress(s, -zlib.MAX_WBITS) without a maximum output limit. This permits unbounded expansion of compressed payloads.
In the JWE decode flow (authlib/authlib/jose/rfc7516/jwe.py), when the protected header contains "zip": "DEF", the library routes the decrypted ciphertext into the decompress method and assigns the fully decompressed bytes to the plaintext field before returning it. No streaming limit or quota is applied.
Because DEFLATE achieves extremely high ratios on highly repetitive input, an attacker can craft a tiny zip=DEF ciphertext that inflates to a very large plaintext during decrypt, spiking RSS and CPU. Repeated requests can starve the process or host.

Code references (from this repository version): - authlib/authlib/jose/rfc7518/jwe_zips.py – DeflateZipAlgorithm.decompress uses unbounded zlib.decompress. - authlib/authlib/jose/rfc7516/jwe.py – JWE decode path applies zip_.decompress(msg) when zip=DEF is present in the header.

Contrast: The joserfc project guards zip=DEF decompression with a fixed maximum (256 KB) and raises ExceededSizeError if output would exceed this limit, preventing the bomb. Authlib lacks such a guard in this codebase snapshot.

PoC

Environment: Python 3.10+ inside a venv; Authlib installed editable from this repository so source changes are visible. The PoC script demonstrates both a benign and a compressible-bomb payload and prints wall/CPU time, RSS, and size ratios.

1) Create venv and install Authlib (editable): Set current directory to /authlib Download jwe_deflate_dos_demo.py in /authlib

python3 -m venv .venv
.venv/bin/pip install --upgrade pip
.venv/bin/pip install -e .

2) Run the PoC (included in this repo):

.venv/bin/python /authlib/jwe_deflate_dos_demo.py --size 50 --max-rss-mb 2048

Sample output (abridged):

LOCAL TEST ONLY – do not send to third-party systems.
Runtime: Python 3.13.6 / Authlib 1.6.4 / zip=DEF via A256GCM
[CASE] normal    plaintext=13B  ciphertext=117B decompressed=13B  wall_s=0.000 cpu_s=0.000 peak_rss_mb=31.0  ratio=0.1
[CASE] malicious plaintext=50MB ciphertext=~4KB decompressed=50MB wall_s=~2.3  cpu_s=~2.2  peak_rss_mb=800+  ratio=12500+

The second case shows the decompression spike: a few KB of ciphertext forces allocation and processing of ~50 MB during decrypt. Repeated requests can quickly exhaust available memory and CPU.

Reproduction notes: - Algorithm: alg=dir, enc=A256GCM, header includes { "zip": "DEF" }. - The PoC uses a 32‑byte local symmetric key and a highly compressible payload ("A" * N). - Increase --size to stress memory; the --max-rss-mb flag helps avoid destabilizing the host during testing.

Impact

Effect: Denial of service (memory/CPU exhaustion) during JWE decrypt of zip=DEF tokens.
Who is impacted: Any service that uses Authlib to decrypt JWE tokens with zip=DEF and where an attacker can submit tokens that will be successfully decrypted (e.g., shared dir key, token reflection, or compromised/abused issuers).
Confidentiality/Integrity: No direct C/I impact; availability impact is high.

Severity (CVSS v3.1)

Base vector (typical shared‑secret scenario where the attacker must produce a decryptable token): - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H → 6.5 (MEDIUM)

Rationale: - Network‑reachable (AV:N), low complexity (AC:L), no user interaction (UI:N), scope unchanged (S:U). - Attacker must hold or gain ability to mint a decryptable token for the target (PR:L) — common with alg=dir and shared keys across services. - No confidentiality or integrity loss (C:N/I:N); availability is severely impacted (A:H) due to decompression expansion. If arbitrary unprivileged parties can submit JWEs that will be decrypted (PR:N), the base vector becomes: - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H → 7.5 (HIGH)

Mitigations / Workarounds

Reject or strip zip=DEF for inbound JWEs at the application boundary until a fix is available.
Fork and add a bounded decompression guard (e.g., zlib.decompress(..., max_length) via decompressobj().decompress(data, MAX_SIZE)), returning an error when output exceeds a safe limit.
Enforce strict maximum token sizes and fail fast on oversized inputs; combine with rate limiting.

Remediation Guidance (for maintainers)

Mirror joserfc’s approach: add a conservative maximum output size (e.g., 256 KB by default) and raise a specific error when exceeded; document a controlled way to raise this ceiling for trusted environments.
Consider streaming decode with chunked limits to avoid large single allocations.

References

Authlib source: authlib/authlib/jose/rfc7518/jwe_zips.py, authlib/authlib/jose/rfc7516/jwe.py

Severity

6.5 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "authlib"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.6.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-62706"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-10-10T22:54:03Z",
    "nvd_published_at": "2025-10-22T22:15:35Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n_Authlib\u2019s JWE `zip=DEF` path performs unbounded DEFLATE decompression. A very small ciphertext can expand into tens or hundreds of megabytes on decrypt, allowing an attacker who can supply decryptable tokens to exhaust memory and CPU and cause denial of service._\n\n### Details\n- Affected component: Authlib JOSE, JWE `zip=DEF` (DEFLATE) support.\n- In `authlib/authlib/jose/rfc7518/jwe_zips.py`, `DeflateZipAlgorithm.decompress` calls `zlib.decompress(s, -zlib.MAX_WBITS)` without a maximum output limit. This permits unbounded expansion of compressed payloads.\n- In the JWE decode flow (`authlib/authlib/jose/rfc7516/jwe.py`), when the protected header contains `\"zip\": \"DEF\"`, the library routes the decrypted ciphertext into the `decompress` method and assigns the fully decompressed bytes to the plaintext field before returning it. No streaming limit or quota is applied.\n- Because DEFLATE achieves extremely high ratios on highly repetitive input, an attacker can craft a tiny `zip=DEF` ciphertext that inflates to a very large plaintext during decrypt, spiking RSS and CPU. Repeated requests can starve the process or host.\n\nCode references (from this repository version):\n- `authlib/authlib/jose/rfc7518/jwe_zips.py` \u2013 `DeflateZipAlgorithm.decompress` uses unbounded `zlib.decompress`.\n- `authlib/authlib/jose/rfc7516/jwe.py` \u2013 JWE decode path applies `zip_.decompress(msg)` when `zip=DEF` is present in the header.\n\nContrast: The `joserfc` project guards `zip=DEF` decompression with a fixed maximum (256 KB) and raises `ExceededSizeError` if output would exceed this limit, preventing the bomb. Authlib lacks such a guard in this codebase snapshot.\n\n### PoC\nEnvironment: Python 3.10+ inside a venv; Authlib installed editable from this repository so source changes are visible. The PoC script demonstrates both a benign and a compressible-bomb payload and prints wall/CPU time, RSS, and size ratios.\n\n1) Create venv and install Authlib (editable):\nSet current directory to /authlib\nDownload [jwe_deflate_dos_demo.py](https://github.com/user-attachments/files/22519553/jwe_deflate_dos_demo.py) in /authlib\n```\npython3 -m venv .venv\n.venv/bin/pip install --upgrade pip\n.venv/bin/pip install -e .\n```\n\n2) Run the PoC (included in this repo):\n```\n.venv/bin/python /authlib/jwe_deflate_dos_demo.py --size 50 --max-rss-mb 2048\n```\n\nSample output (abridged):\n```\nLOCAL TEST ONLY \u2013 do not send to third-party systems.\nRuntime: Python 3.13.6 / Authlib 1.6.4 / zip=DEF via A256GCM\n[CASE] normal    plaintext=13B  ciphertext=117B decompressed=13B  wall_s=0.000 cpu_s=0.000 peak_rss_mb=31.0  ratio=0.1\n[CASE] malicious plaintext=50MB ciphertext=~4KB decompressed=50MB wall_s=~2.3  cpu_s=~2.2  peak_rss_mb=800+  ratio=12500+\n```\n\nThe second case shows the decompression spike: a few KB of ciphertext forces allocation and processing of ~50 MB during decrypt. Repeated requests can quickly exhaust available memory and CPU.\n\nReproduction notes:\n- Algorithm: `alg=dir`, `enc=A256GCM`, header includes `{ \"zip\": \"DEF\" }`.\n- The PoC uses a 32\u2011byte local symmetric key and a highly compressible payload (`\"A\" * N`).\n- Increase `--size` to stress memory; the `--max-rss-mb` flag helps avoid destabilizing the host during testing.\n\n### Impact\n- Effect: Denial of service (memory/CPU exhaustion) during JWE decrypt of `zip=DEF` tokens.\n- Who is impacted: Any service that uses Authlib to decrypt JWE tokens with `zip=DEF` and where an attacker can submit tokens that will be successfully decrypted (e.g., shared `dir` key, token reflection, or compromised/abused issuers).\n- Confidentiality/Integrity: No direct C/I impact; availability impact is high.\n\n### Severity (CVSS v3.1)\nBase vector (typical shared\u2011secret scenario where the attacker must produce a decryptable token):\n- `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H` \u2192 6.5 (MEDIUM)\n\n**Rationale:**\n- Network\u2011reachable (AV:N), low complexity (AC:L), no user interaction (UI:N), scope unchanged (S:U).\n- Attacker must hold or gain ability to mint a decryptable token for the target (PR:L) \u2014 common with `alg=dir` and shared keys across services.\n- No confidentiality or integrity loss (C:N/I:N); availability is severely impacted (A:H) due to decompression expansion.\nIf arbitrary unprivileged parties can submit JWEs that will be decrypted (PR:N), the base vector becomes:\n- `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H` \u2192 7.5 (HIGH)\n\n### Mitigations / Workarounds\n- Reject or strip `zip=DEF` for inbound JWEs at the application boundary until a fix is available.\n- Fork and add a bounded decompression guard (e.g., `zlib.decompress(..., max_length)` via `decompressobj().decompress(data, MAX_SIZE)`), returning an error when output exceeds a safe limit.\n- Enforce strict maximum token sizes and fail fast on oversized inputs; combine with rate limiting.\n\n### Remediation Guidance (for maintainers)\n- Mirror `joserfc`\u2019s approach: add a conservative maximum output size (e.g., 256 KB by default) and raise a specific error when exceeded; document a controlled way to raise this ceiling for trusted environments.\n- Consider streaming decode with chunked limits to avoid large single allocations.\n\n### References\n- Authlib source: `authlib/authlib/jose/rfc7518/jwe_zips.py`, `authlib/authlib/jose/rfc7516/jwe.py`",
  "id": "GHSA-g7f3-828f-7h7m",
  "modified": "2025-11-03T18:31:46Z",
  "published": "2025-10-10T22:54:03Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/authlib/authlib/security/advisories/GHSA-g7f3-828f-7h7m"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-62706"
    },
    {
      "type": "WEB",
      "url": "https://github.com/authlib/authlib/commit/e0863d5129316b1790eee5f14cece32a03b8184d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/authlib/authlib"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00032.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Authlib : JWE zip=DEF decompression bomb enables DoS"
}

GHSA-G84X-MCQJ-X9QQ

Vulnerability from github – Published: 2026-01-05 23:13 – Updated: 2026-01-06 16:06

Summary

AIOHTTP vulnerable to DoS through chunked messages

Details

Summary

Handling of chunked messages can result in excessive blocking CPU usage when receiving a large number of chunks.

Impact

If an application makes use of the request.read() method in an endpoint, it may be possible for an attacker to cause the server to spend a moderate amount of blocking CPU time (e.g. 1 second) while processing the request. This could potentially lead to DoS as the server would be unable to handle other requests during that time.

Patch: https://github.com/aio-libs/aiohttp/commit/dc3170b56904bdf814228fae70a5501a42a6c712 Patch: https://github.com/aio-libs/aiohttp/commit/4ed97a4e46eaf61bd0f05063245f613469700229

Severity

6.6 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 3.13.2"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "aiohttp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.13.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-69229"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-05T23:13:29Z",
    "nvd_published_at": "2026-01-06T00:15:48Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nHandling of chunked messages can result in excessive blocking CPU usage when receiving a large number of chunks.\n\n### Impact\n\nIf an application makes use of the `request.read()` method in an endpoint, it may be possible for an attacker to cause the server to spend a moderate amount of blocking CPU time (e.g. 1 second) while processing the request. This could potentially lead to DoS as the server would be unable to handle other requests during that time.\n\n-----\n\nPatch: https://github.com/aio-libs/aiohttp/commit/dc3170b56904bdf814228fae70a5501a42a6c712\nPatch: https://github.com/aio-libs/aiohttp/commit/4ed97a4e46eaf61bd0f05063245f613469700229",
  "id": "GHSA-g84x-mcqj-x9qq",
  "modified": "2026-01-06T16:06:58Z",
  "published": "2026-01-05T23:13:29Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-g84x-mcqj-x9qq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-69229"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/commit/4ed97a4e46eaf61bd0f05063245f613469700229"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/commit/dc3170b56904bdf814228fae70a5501a42a6c712"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/aio-libs/aiohttp"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "AIOHTTP vulnerable to DoS through chunked messages"
}

GHSA-G85R-6X2Q-45W7

Vulnerability from github – Published: 2024-04-15 20:22 – Updated: 2025-01-09 22:04

Summary

SixLabors.ImageSharp vulnerable to Memory Allocation with Excessive Size Value

Details

Impact

A vulnerability discovered in the ImageSharp library, where the processing of specially crafted files can lead to excessive memory usage in image decoders. The vulnerability is triggered when ImageSharp attempts to process image files that are designed to exploit this flaw.

This flaw can be exploited to cause a denial of service (DoS) by depleting process memory, thereby affecting applications and services that rely on ImageSharp for image processing tasks. Users and administrators are advised to update to the latest version of ImageSharp that addresses this vulnerability to mitigate the risk of exploitation.

Patches

The problem has been patched. All users are advised to upgrade to v3.1.4 or v2.1.8.

Workarounds

Before calling Image.Decode(Async), use Image.Identify to determine the image dimensions in order to enforce a limit.

References

ImageSharp: Security Considerations
ImageSharp.Web: Securing Processing Commands

Severity

5.3 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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{
  "affected": [
    {
      "package": {
        "ecosystem": "NuGet",
        "name": "SixLabors.ImageSharp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "NuGet",
        "name": "SixLabors.ImageSharp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "fixed": "3.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-32035"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770",
      "CWE-789"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-04-15T20:22:54Z",
    "nvd_published_at": "2024-04-15T20:15:11Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nA vulnerability discovered in the ImageSharp library, where the processing of specially crafted files can lead to excessive memory usage in image decoders. The vulnerability is triggered when ImageSharp attempts to process image files that are designed to exploit this flaw. \n\nThis flaw can be exploited to cause a denial of service (DoS) by depleting process memory, thereby affecting applications and services that rely on ImageSharp for image processing tasks. Users and administrators are advised to update to the latest version of ImageSharp that addresses this vulnerability to mitigate the risk of exploitation.\n\n### Patches\n\nThe problem has been patched. All users are advised to upgrade to v3.1.4 or v2.1.8.\n\n### Workarounds\n\nBefore calling `Image.Decode(Async)`, use `Image.Identify` to determine the image dimensions in order to enforce a limit.\n\n### References\n\n- ImageSharp: [Security Considerations](https://docs.sixlabors.com/articles/imagesharp/security.html)\n- ImageSharp.Web: [Securing Processing Commands](https://docs.sixlabors.com/articles/imagesharp.web/processingcommands.html#securing-processing-commands)",
  "id": "GHSA-g85r-6x2q-45w7",
  "modified": "2025-01-09T22:04:41Z",
  "published": "2024-04-15T20:22:54Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/SixLabors/ImageSharp/security/advisories/GHSA-g85r-6x2q-45w7"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-32035"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SixLabors/ImageSharp/commit/b6b08ac3e7cea8da5ac1e90f7c0b67dd254535c3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SixLabors/ImageSharp/commit/f21d64188e59ae9464ff462056a5e29d8e618b27"
    },
    {
      "type": "WEB",
      "url": "https://docs.sixlabors.com/articles/imagesharp.web/processingcommands.html#securing-processing-commands"
    },
    {
      "type": "WEB",
      "url": "https://docs.sixlabors.com/articles/imagesharp/security.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/SixLabors/ImageSharp"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "SixLabors.ImageSharp vulnerable to Memory Allocation with Excessive Size Value"
}

GHSA-G877-JJJQ-5FJC

Vulnerability from github – Published: 2024-08-17 12:30 – Updated: 2026-05-12 12:32

Details

In the Linux kernel, the following vulnerability has been resolved:

dma: fix call order in dmam_free_coherent

dmam_free_coherent() frees a DMA allocation, which makes the freed vaddr available for reuse, then calls devres_destroy() to remove and free the data structure used to track the DMA allocation. Between the two calls, it is possible for a concurrent task to make an allocation with the same vaddr and add it to the devres list.

If this happens, there will be two entries in the devres list with the same vaddr and devres_destroy() can free the wrong entry, triggering the WARN_ON() in dmam_match.

Fix by destroying the devres entry before freeing the DMA allocation.

kokonut //net/encryption http://sponge2/b9145fe6-0f72-4325-ac2f-a84d81075b03

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2024-43856"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-08-17T10:15:10Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndma: fix call order in dmam_free_coherent\n\ndmam_free_coherent() frees a DMA allocation, which makes the\nfreed vaddr available for reuse, then calls devres_destroy()\nto remove and free the data structure used to track the DMA\nallocation. Between the two calls, it is possible for a\nconcurrent task to make an allocation with the same vaddr\nand add it to the devres list.\n\nIf this happens, there will be two entries in the devres list\nwith the same vaddr and devres_destroy() can free the wrong\nentry, triggering the WARN_ON() in dmam_match.\n\nFix by destroying the devres entry before freeing the DMA\nallocation.\n\n  kokonut //net/encryption\n    http://sponge2/b9145fe6-0f72-4325-ac2f-a84d81075b03",
  "id": "GHSA-g877-jjjq-5fjc",
  "modified": "2026-05-12T12:32:04Z",
  "published": "2024-08-17T12:30:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-43856"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1fe97f68fce1ba24bf823bfb0eb0956003473130"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/22094f5f52e7bc16c5bf9613365049383650b02e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/257193083e8f43907e99ea633820fc2b3bcd24c7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/28e8b7406d3a1f5329a03aa25a43aa28e087cb20"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2f7bbdc744f2e7051d1cb47c8e082162df1923c9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/87b34c8c94e29fa01d744e5147697f592998d954"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f993a4baf6b622232e4c190d34c220179e5d61eb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fe2d246080f035e0af5793cb79067ba125e4fb63"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G8C4-6CM2-MVXV

Vulnerability from github – Published: 2022-04-16 00:00 – Updated: 2022-05-17 00:01

Details

A vulnerability in the NETCONF process of Cisco SD-WAN vEdge Routers could allow an authenticated, local attacker to cause an affected device to run out of memory, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient memory management when an affected device receives large amounts of traffic. An attacker could exploit this vulnerability by sending malicious traffic to an affected device. A successful exploit could allow the attacker to cause the device to crash, resulting in a DoS condition.

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2022-20717"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770",
      "CWE-789"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-04-15T15:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability in the NETCONF process of Cisco SD-WAN vEdge Routers could allow an authenticated, local attacker to cause an affected device to run out of memory, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient memory management when an affected device receives large amounts of traffic. An attacker could exploit this vulnerability by sending malicious traffic to an affected device. A successful exploit could allow the attacker to cause the device to crash, resulting in a DoS condition.",
  "id": "GHSA-g8c4-6cm2-mvxv",
  "modified": "2022-05-17T00:01:43Z",
  "published": "2022-04-16T00:00:50Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-20717"
    },
    {
      "type": "WEB",
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-vedge-dos-jerVm4bB"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G8GX-VMX9-6PJP

Vulnerability from github – Published: 2023-06-22 15:30 – Updated: 2024-04-04 05:01

Details

An issue in the GDKfree component of MonetDB Server v11.45.17 and v11.46.0 allows attackers to cause a Denial of Service (DoS) via crafted SQL statements.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2023-36371"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-06-22T14:15:10Z",
    "severity": "HIGH"
  },
  "details": "An issue in the GDKfree component of MonetDB Server v11.45.17 and v11.46.0 allows attackers to cause a Denial of Service (DoS) via crafted SQL statements.",
  "id": "GHSA-g8gx-vmx9-6pjp",
  "modified": "2024-04-04T05:01:06Z",
  "published": "2023-06-22T15:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-36371"
    },
    {
      "type": "WEB",
      "url": "https://github.com/MonetDB/MonetDB/issues/7385"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G8M5-722R-8WHQ

Vulnerability from github – Published: 2024-10-14 21:08 – Updated: 2025-11-03 22:49

Summary

Eclipse Jetty's ThreadLimitHandler.getRemote() vulnerable to remote DoS attacks

Details

Impact

Remote DOS attack can cause out of memory

Description

There exists a security vulnerability in Jetty's ThreadLimitHandler.getRemote() which can be exploited by unauthorized users to cause remote denial-of-service (DoS) attack. By repeatedly sending crafted requests, attackers can trigger OutofMemory errors and exhaust the server's memory.

Affected Versions

Jetty 12.0.0-12.0.8 (Supported)
Jetty 11.0.0-11.0.23 (EOL)
Jetty 10.0.0-10.0.23 (EOL)
Jetty 9.3.12-9.4.55 (EOL)

Patched Versions

Jetty 12.0.9
Jetty 11.0.24
Jetty 10.0.24
Jetty 9.4.56

Workarounds

Do not use ThreadLimitHandler.
Consider use of QoSHandler instead to artificially limit resource utilization.

References

Jetty 12 - https://github.com/jetty/jetty.project/pull/11723

Severity

5.9 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 12.0.8"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "12.0.0"
            },
            {
              "fixed": "12.0.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 10.0.23"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.24"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 11.0.23"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "11.0.0"
            },
            {
              "fixed": "11.0.24"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 9.4.55"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "9.3.12"
            },
            {
              "fixed": "9.4.56"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-8184"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-10-14T21:08:38Z",
    "nvd_published_at": "2024-10-14T16:15:04Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nRemote DOS attack can cause out of memory \n\n### Description\nThere exists a security vulnerability in Jetty\u0027s `ThreadLimitHandler.getRemote()` which\ncan be exploited by unauthorized users to cause remote denial-of-service (DoS) attack.  By\nrepeatedly sending crafted requests, attackers can trigger OutofMemory errors and exhaust the\nserver\u0027s memory.\n\n### Affected Versions\n\n* Jetty 12.0.0-12.0.8 (Supported)\n* Jetty 11.0.0-11.0.23 (EOL)\n* Jetty 10.0.0-10.0.23 (EOL)\n* Jetty 9.3.12-9.4.55 (EOL)\n\n### Patched Versions\n\n* Jetty 12.0.9\n* Jetty 11.0.24\n* Jetty 10.0.24\n* Jetty 9.4.56\n\n### Workarounds\n\nDo not use `ThreadLimitHandler`.  \nConsider use of `QoSHandler` instead to artificially limit resource utilization.\n\n### References\n\nJetty 12 - https://github.com/jetty/jetty.project/pull/11723",
  "id": "GHSA-g8m5-722r-8whq",
  "modified": "2025-11-03T22:49:11Z",
  "published": "2024-10-14T21:08:38Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jetty/jetty.project/security/advisories/GHSA-g8m5-722r-8whq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-8184"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jetty/jetty.project/pull/11723"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jetty/jetty.project"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.eclipse.org/security/cve-assignement/-/issues/30"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/04/msg00001.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Eclipse Jetty\u0027s ThreadLimitHandler.getRemote() vulnerable to remote DoS attacks"
}

GHSA-G92R-8X2F-9V8M

Vulnerability from github – Published: 2024-08-07 18:30 – Updated: 2024-08-08 15:31

Details

In the Linux kernel, the following vulnerability has been resolved:

mmc: sdhci: Fix max_seg_size for 64KiB PAGE_SIZE

blk_queue_max_segment_size() ensured:

if (max_size < PAGE_SIZE)
    max_size = PAGE_SIZE;

whereas:

blk_validate_limits() makes it an error:

if (WARN_ON_ONCE(lim->max_segment_size < PAGE_SIZE))
    return -EINVAL;

The change from one to the other, exposed sdhci which was setting maximum segment size too low in some circumstances.

Fix the maximum segment size when it is too low.

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2024-42242"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-08-07T16:15:47Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmmc: sdhci: Fix max_seg_size for 64KiB PAGE_SIZE\n\nblk_queue_max_segment_size() ensured:\n\n\tif (max_size \u003c PAGE_SIZE)\n\t\tmax_size = PAGE_SIZE;\n\nwhereas:\n\nblk_validate_limits() makes it an error:\n\n\tif (WARN_ON_ONCE(lim-\u003emax_segment_size \u003c PAGE_SIZE))\n\t\treturn -EINVAL;\n\nThe change from one to the other, exposed sdhci which was setting maximum\nsegment size too low in some circumstances.\n\nFix the maximum segment size when it is too low.",
  "id": "GHSA-g92r-8x2f-9v8m",
  "modified": "2024-08-08T15:31:29Z",
  "published": "2024-08-07T18:30:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-42242"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/63d20a94f24fc1cbaf44d0e7c0e0a8077fde0aef"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bf78b1accef46efd9b624967cb74ae8d3c215a2b"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G93F-RHW4-8MJ3

Vulnerability from github – Published: 2025-05-22 15:34 – Updated: 2025-05-22 15:34

Details

An issue has been discovered in GitLab CE/EE affecting all versions before 17.10.7, 17.11 before 17.11.3, and 18.0 before 18.0.1. This could allow an authenticated attacker to cause a denial of service condition by exhausting server resources.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2025-0993"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-22T15:16:04Z",
    "severity": "HIGH"
  },
  "details": "An issue has been discovered in GitLab CE/EE affecting all versions before 17.10.7, 17.11 before 17.11.3, and 18.0 before 18.0.1. This could allow an authenticated attacker to cause a denial of service condition by exhausting server resources.",
  "id": "GHSA-g93f-rhw4-8mj3",
  "modified": "2025-05-22T15:34:51Z",
  "published": "2025-05-22T15:34:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-0993"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/2967771"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/gitlab/-/issues/516927"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G9F8-WQJ9-FJW5

Vulnerability from github – Published: 2026-05-21 20:49 – Updated: 2026-06-11 14:06

Summary

Russh: Unchecked CryptoVec allocation and growth handling is reachable

Details

Title

Unchecked CryptoVec allocation and growth handling was reachable from local agent inputs in current russh releases and from remote SSH traffic in historical pre-0.58.0 releases

Summary

CryptoVec used unchecked capacity growth, unchecked length arithmetic, and unsafe allocation/locking paths. In current russh releases, local SSH agent peers could still feed attacker-controlled frame lengths into buffer growth before validation. In older russh releases before 0.58.0, remote SSH traffic also reached CryptoVec through transport and compression buffers.

Details

The underlying unsafe paths were in CryptoVec:

cryptovec/src/cryptovec.rs
unchecked capacity growth
unchecked length arithmetic in growth callers
raw allocation and reallocation paths coupled to those sizes
cryptovec/src/platform/unix.rs
mlock / munlock previously accepted zero-length calls and performed null-pointer validation inside the unsafe OS-call path

There are two relevant reachability stories:

current local reachability in russh
russh/src/keys/agent/client.rs
AgentClient::read_response() read a peer-supplied u32 length and then resized self.buf to that value before reading the payload
russh/src/keys/agent/server.rs
Connection::run() read a peer-supplied u32 length and then resized self.buf to that value before reading the payload

This is the path that still existed in current 0.60.x releases before the fix, although by then those buffers were no longer CryptoVec.

historical remote reachability in older russh
before commit 712e32b (first released in v0.58.0), non-secret transport and compression buffers in russh still used CryptoVec
I verified this in a detached pre-712e32b worktree by adding and running:
cipher::tests::remote_packet_length_grows_transport_cryptovec_buffer
compression::tests::remote_compressed_payload_expands_cryptovec_output
those tests show that remote SSH traffic could grow CryptoVec through:
transport packet reads
zlib decompression output

Also added a constrained-memory reproduction in that historical worktree:

compression::tests::remote_compressed_payload_can_crash_under_memory_limit

That test re-execs the test binary under prlimit --as=134217728, decompresses a highly compressible payload that expands to 96 MiB, and reliably aborts in the old Unix CryptoVec path when NonNull::new_unchecked() receives a null pointer after allocation failure.

The prepared patch does two things:

hardens CryptoVec itself
checked capacity growth
checked length arithmetic
immediate allocation-failure handling
zero-length mlock / munlock no-ops
explicit null-pointer validation before entering the Unix unsafe locking calls
hardens the real untrusted-input path
caps agent frame lengths at 256 * 1024 on both client and server before resizing buffers

This cap matches OpenSSH’s agent framing guardrail.

PoC

The following end-to-end tests demonstrate the real untrusted-input path by feeding oversized peer-controlled agent frame lengths into the public client and server flows and asserting that they are rejected before buffer growth.

Client-side agent reply path:

#[test]
fn oversized_agent_response_is_rejected_before_allocation() -> std::io::Result<()> {
    let runtime = tokio::runtime::Builder::new_current_thread()
        .enable_all()
        .build()?;

    runtime.block_on(async {
        let (mut writer, reader) = tokio::io::duplex(64);
        let server = tokio::spawn(async move {
            let mut frame = [0u8; 4];
            writer.read_exact(&mut frame).await?;
            let len = BigEndian::read_u32(&frame) as usize;
            let mut body = vec![0; len];
            writer.read_exact(&mut body).await?;

            BigEndian::write_u32(&mut frame, (MAX_AGENT_FRAME_LEN + 1) as u32);
            writer.write_all(&frame).await?;
            Ok::<(), std::io::Error>(())
        });

        let mut client = AgentClient::connect(reader);
        let err = client.request_identities().await.unwrap_err();
        assert!(matches!(err, Error::AgentProtocolError));
        server.await.expect("server task")?;
        Ok::<(), std::io::Error>(())
    })?;

    Ok(())
}

Server-side agent request path:

#[test]
fn oversized_agent_request_is_rejected_before_allocation() -> std::io::Result<()> {
    let runtime = tokio::runtime::Builder::new_current_thread()
        .enable_all()
        .build()?;

    runtime.block_on(async {
        let (server, mut client) = tokio::io::duplex(64);
        let connection = Connection {
            lock: Lock(std::sync::Arc::new(std::sync::RwLock::new(crate::CryptoVec::new()))),
            keys: KeyStore(std::sync::Arc::new(std::sync::RwLock::new(
                std::collections::HashMap::new(),
            ))),
            agent: Some(()),
            s: server,
            buf: Vec::new(),
        };
        let server = tokio::spawn(async move { connection.run().await });

        let mut frame = [0u8; 4];
        BigEndian::write_u32(&mut frame, (MAX_AGENT_FRAME_LEN + 1) as u32);
        client.write_all(&frame).await?;
        drop(client);

        let err = server.await.expect("server task").unwrap_err();
        assert!(matches!(err, Error::AgentProtocolError));
        Ok::<(), std::io::Error>(())
    })?;

    Ok(())
}

These tests pass on the fixed branch and fail on unfixed v0.60.2, where oversized agent frame lengths are not rejected at the framing boundary.

For historical russh < 0.58.0, I also verified remote reachability into CryptoVec in a detached pre-712e32b worktree (91d431d, package version 0.57.1).

Transport packet read path:

#[test]
fn remote_packet_length_grows_transport_cryptovec_buffer() -> std::io::Result<()> {
    let runtime = tokio::runtime::Builder::new_current_thread()
        .enable_all()
        .build()?;

    runtime.block_on(async {
        let packet_len = MAXIMUM_PACKET_LEN;
        let (mut writer, mut reader) = tokio::io::duplex(packet_len + 4);
        let writer_task = tokio::spawn(async move {
            let mut packet = vec![0u8; packet_len + 4];
            packet[..4].copy_from_slice(&(packet_len as u32).to_be_bytes());
            writer.write_all(&packet).await?;
            Ok::<(), std::io::Error>(())
        });

        let mut buffer = SSHBuffer::new();
        let mut cipher = clear::Key;
        let n = read(&mut reader, &mut buffer, &mut cipher).await.unwrap();

        assert_eq!(n, packet_len + 4);
        assert_eq!(buffer.buffer.len(), packet_len + 4);
        assert_eq!(&buffer.buffer[..4], &(packet_len as u32).to_be_bytes());

        writer_task.await.expect("writer task")?;
        Ok::<(), std::io::Error>(())
    })?;

    Ok(())
}

Compression growth path:

#[test]
fn remote_compressed_payload_expands_cryptovec_output() {
    let payload = vec![b'A'; 64 * 1024];

    let compression = Compression::new(&ZLIB);
    let mut compressor = Compress::None;
    let mut decompressor = Decompress::None;
    compression.init_compress(&mut compressor);
    compression.init_decompress(&mut decompressor);

    let mut compressed = CryptoVec::new();
    let encoded = compressor
        .compress(&payload, &mut compressed)
        .expect("compress")
        .to_vec();

    let mut output = CryptoVec::new();
    let decoded = decompressor
        .decompress(&encoded, &mut output)
        .expect("decompress");

    assert_eq!(decoded.len(), payload.len());
    assert_eq!(decoded, payload.as_slice());
    assert!(encoded.len() < output.len());
}

Constrained-memory crash reproduction for the historical remote compression path:

#[test]
fn remote_compressed_payload_can_crash_under_memory_limit() {
    const CHILD_ENV: &str = "RUSSH_REMOTE_COMPRESS_CRASH_CHILD";

    if std::env::var_os(CHILD_ENV).is_some() {
        let payload = vec![b'A'; 96 * 1024 * 1024];

        let compression = Compression::new(&ZLIB);
        let mut compressor = Compress::None;
        let mut decompressor = Decompress::None;
        compression.init_compress(&mut compressor);
        compression.init_decompress(&mut decompressor);

        let mut compressed = CryptoVec::new();
        let encoded = compressor
            .compress(&payload, &mut compressed)
            .expect("compress")
            .to_vec();

        let mut output = CryptoVec::new();
        let decoded = decompressor
            .decompress(&encoded, &mut output)
            .expect("decompress");
        assert_eq!(decoded.len(), payload.len());
        return;
    }

    let exe = std::env::current_exe().expect("current exe");
    let status = Command::new("prlimit")
        .args([
            "--as=134217728",
            "--",
            exe.to_str().expect("utf8 exe path"),
            "--exact",
            "compression::tests::remote_compressed_payload_can_crash_under_memory_limit",
            "--nocapture",
        ])
        .env(CHILD_ENV, "1")
        .status()
        .expect("spawn child");

    assert!(
        !status.success(),
        "expected child to fail under constrained address space"
    );
}

On that historical worktree, the constrained-memory child aborts in the old Unix CryptoVec path with:

unsafe precondition(s) violated: NonNull::new_unchecked requires that the pointer is non-null
thread caused non-unwinding panic. aborting.

To run the reproduced checks:

cargo test -p russh oversized_agent_response_is_rejected_before_allocation -- --nocapture
cargo test -p russh oversized_agent_request_is_rejected_before_allocation -- --nocapture
cargo test -p russh-cryptovec

Historical pre-0.58.0 checks were run from the detached 91d431d worktree with:

cargo test --offline -p russh remote_packet_length_grows_transport_cryptovec_buffer -- --nocapture
cargo test --offline -p russh remote_compressed_payload_expands_cryptovec_output -- --nocapture
cargo test --offline -p russh remote_compressed_payload_can_crash_under_memory_limit -- --nocapture

Impact

This is a memory-safety hardening issue with demonstrated untrusted-input reachability.

What is demonstrated:

current local agent peers could previously reach allocation growth directly from attacker-controlled frame lengths
historical remote SSH traffic could previously reach CryptoVec through transport and compression buffers in russh < 0.58.0
under constrained memory, the historical remote compression path can be turned into a process abort in the old Unix CryptoVec code
the fixed code now rejects oversized agent frames early and hardens the underlying allocation paths

What is not demonstrated:

practical code execution
a demonstrated integrity or confidentiality break

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.60.2"
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "russh-cryptovec"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.60.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.60.2"
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "russh"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.60.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-46673"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-21T20:49:07Z",
    "nvd_published_at": "2026-06-10T22:17:00Z",
    "severity": "HIGH"
  },
  "details": "### Title\nUnchecked `CryptoVec` allocation and growth handling was reachable from local agent inputs in current `russh` releases and from remote SSH traffic in historical pre-`0.58.0` releases\n\n### Summary\n`CryptoVec` used unchecked capacity growth, unchecked length arithmetic, and unsafe allocation/locking paths. In current `russh` releases, local SSH agent peers could still feed attacker-controlled frame lengths into buffer growth before validation. In older `russh` releases before `0.58.0`, remote SSH traffic also reached `CryptoVec` through transport and compression buffers.\n\n### Details\nThe underlying unsafe paths were in `CryptoVec`:\n\n- `cryptovec/src/cryptovec.rs`\n  - unchecked capacity growth\n  - unchecked length arithmetic in growth callers\n  - raw allocation and reallocation paths coupled to those sizes\n- `cryptovec/src/platform/unix.rs`\n  - `mlock` / `munlock` previously accepted zero-length calls and performed null-pointer validation inside the `unsafe` OS-call path\n\nThere are two relevant reachability stories:\n\n1. current local reachability in `russh`\n\n- `russh/src/keys/agent/client.rs`\n  - `AgentClient::read_response()` read a peer-supplied `u32` length and then resized `self.buf` to that value before reading the payload\n- `russh/src/keys/agent/server.rs`\n  - `Connection::run()` read a peer-supplied `u32` length and then resized `self.buf` to that value before reading the payload\n\nThis is the path that still existed in current `0.60.x` releases before the fix, although by then those buffers were no longer `CryptoVec`.\n\n2. historical remote reachability in older `russh`\n\n- before commit `712e32b` (first released in `v0.58.0`), non-secret transport and compression buffers in `russh` still used `CryptoVec`\n- I verified this in a detached pre-`712e32b` worktree by adding and running:\n  - `cipher::tests::remote_packet_length_grows_transport_cryptovec_buffer`\n  - `compression::tests::remote_compressed_payload_expands_cryptovec_output`\n- those tests show that remote SSH traffic could grow `CryptoVec` through:\n  - transport packet reads\n  - zlib decompression output\n\nAlso added a constrained-memory reproduction in that historical worktree:\n\n- `compression::tests::remote_compressed_payload_can_crash_under_memory_limit`\n\nThat test re-execs the test binary under `prlimit --as=134217728`, decompresses a highly compressible payload that expands to `96 MiB`, and reliably aborts in the old Unix `CryptoVec` path when `NonNull::new_unchecked()` receives a null pointer after allocation failure.\n\nThe prepared patch does two things:\n\n1. hardens `CryptoVec` itself\n   - checked capacity growth\n   - checked length arithmetic\n   - immediate allocation-failure handling\n   - zero-length `mlock` / `munlock` no-ops\n   - explicit null-pointer validation before entering the Unix `unsafe` locking calls\n\n2. hardens the real untrusted-input path\n   - caps agent frame lengths at `256 * 1024` on both client and server before resizing buffers\n\nThis cap matches OpenSSH\u2019s agent framing guardrail.\n\n### PoC\nThe following end-to-end tests demonstrate the real untrusted-input path by feeding oversized peer-controlled agent frame lengths into the public client and server flows and asserting that they are rejected before buffer growth.\n\nClient-side agent reply path:\n\n```rust\n#[test]\nfn oversized_agent_response_is_rejected_before_allocation() -\u003e std::io::Result\u003c()\u003e {\n    let runtime = tokio::runtime::Builder::new_current_thread()\n        .enable_all()\n        .build()?;\n\n    runtime.block_on(async {\n        let (mut writer, reader) = tokio::io::duplex(64);\n        let server = tokio::spawn(async move {\n            let mut frame = [0u8; 4];\n            writer.read_exact(\u0026mut frame).await?;\n            let len = BigEndian::read_u32(\u0026frame) as usize;\n            let mut body = vec![0; len];\n            writer.read_exact(\u0026mut body).await?;\n\n            BigEndian::write_u32(\u0026mut frame, (MAX_AGENT_FRAME_LEN + 1) as u32);\n            writer.write_all(\u0026frame).await?;\n            Ok::\u003c(), std::io::Error\u003e(())\n        });\n\n        let mut client = AgentClient::connect(reader);\n        let err = client.request_identities().await.unwrap_err();\n        assert!(matches!(err, Error::AgentProtocolError));\n        server.await.expect(\"server task\")?;\n        Ok::\u003c(), std::io::Error\u003e(())\n    })?;\n\n    Ok(())\n}\n```\n\nServer-side agent request path:\n\n```rust\n#[test]\nfn oversized_agent_request_is_rejected_before_allocation() -\u003e std::io::Result\u003c()\u003e {\n    let runtime = tokio::runtime::Builder::new_current_thread()\n        .enable_all()\n        .build()?;\n\n    runtime.block_on(async {\n        let (server, mut client) = tokio::io::duplex(64);\n        let connection = Connection {\n            lock: Lock(std::sync::Arc::new(std::sync::RwLock::new(crate::CryptoVec::new()))),\n            keys: KeyStore(std::sync::Arc::new(std::sync::RwLock::new(\n                std::collections::HashMap::new(),\n            ))),\n            agent: Some(()),\n            s: server,\n            buf: Vec::new(),\n        };\n        let server = tokio::spawn(async move { connection.run().await });\n\n        let mut frame = [0u8; 4];\n        BigEndian::write_u32(\u0026mut frame, (MAX_AGENT_FRAME_LEN + 1) as u32);\n        client.write_all(\u0026frame).await?;\n        drop(client);\n\n        let err = server.await.expect(\"server task\").unwrap_err();\n        assert!(matches!(err, Error::AgentProtocolError));\n        Ok::\u003c(), std::io::Error\u003e(())\n    })?;\n\n    Ok(())\n}\n```\n\nThese tests pass on the fixed branch and fail on unfixed `v0.60.2`, where oversized agent frame lengths are not rejected at the framing boundary.\n\nFor historical `russh \u003c 0.58.0`, I also verified remote reachability into `CryptoVec` in a detached pre-`712e32b` worktree (`91d431d`, package version `0.57.1`).\n\nTransport packet read path:\n\n```rust\n#[test]\nfn remote_packet_length_grows_transport_cryptovec_buffer() -\u003e std::io::Result\u003c()\u003e {\n    let runtime = tokio::runtime::Builder::new_current_thread()\n        .enable_all()\n        .build()?;\n\n    runtime.block_on(async {\n        let packet_len = MAXIMUM_PACKET_LEN;\n        let (mut writer, mut reader) = tokio::io::duplex(packet_len + 4);\n        let writer_task = tokio::spawn(async move {\n            let mut packet = vec![0u8; packet_len + 4];\n            packet[..4].copy_from_slice(\u0026(packet_len as u32).to_be_bytes());\n            writer.write_all(\u0026packet).await?;\n            Ok::\u003c(), std::io::Error\u003e(())\n        });\n\n        let mut buffer = SSHBuffer::new();\n        let mut cipher = clear::Key;\n        let n = read(\u0026mut reader, \u0026mut buffer, \u0026mut cipher).await.unwrap();\n\n        assert_eq!(n, packet_len + 4);\n        assert_eq!(buffer.buffer.len(), packet_len + 4);\n        assert_eq!(\u0026buffer.buffer[..4], \u0026(packet_len as u32).to_be_bytes());\n\n        writer_task.await.expect(\"writer task\")?;\n        Ok::\u003c(), std::io::Error\u003e(())\n    })?;\n\n    Ok(())\n}\n```\n\nCompression growth path:\n\n```rust\n#[test]\nfn remote_compressed_payload_expands_cryptovec_output() {\n    let payload = vec![b\u0027A\u0027; 64 * 1024];\n\n    let compression = Compression::new(\u0026ZLIB);\n    let mut compressor = Compress::None;\n    let mut decompressor = Decompress::None;\n    compression.init_compress(\u0026mut compressor);\n    compression.init_decompress(\u0026mut decompressor);\n\n    let mut compressed = CryptoVec::new();\n    let encoded = compressor\n        .compress(\u0026payload, \u0026mut compressed)\n        .expect(\"compress\")\n        .to_vec();\n\n    let mut output = CryptoVec::new();\n    let decoded = decompressor\n        .decompress(\u0026encoded, \u0026mut output)\n        .expect(\"decompress\");\n\n    assert_eq!(decoded.len(), payload.len());\n    assert_eq!(decoded, payload.as_slice());\n    assert!(encoded.len() \u003c output.len());\n}\n```\n\nConstrained-memory crash reproduction for the historical remote compression path:\n\n```rust\n#[test]\nfn remote_compressed_payload_can_crash_under_memory_limit() {\n    const CHILD_ENV: \u0026str = \"RUSSH_REMOTE_COMPRESS_CRASH_CHILD\";\n\n    if std::env::var_os(CHILD_ENV).is_some() {\n        let payload = vec![b\u0027A\u0027; 96 * 1024 * 1024];\n\n        let compression = Compression::new(\u0026ZLIB);\n        let mut compressor = Compress::None;\n        let mut decompressor = Decompress::None;\n        compression.init_compress(\u0026mut compressor);\n        compression.init_decompress(\u0026mut decompressor);\n\n        let mut compressed = CryptoVec::new();\n        let encoded = compressor\n            .compress(\u0026payload, \u0026mut compressed)\n            .expect(\"compress\")\n            .to_vec();\n\n        let mut output = CryptoVec::new();\n        let decoded = decompressor\n            .decompress(\u0026encoded, \u0026mut output)\n            .expect(\"decompress\");\n        assert_eq!(decoded.len(), payload.len());\n        return;\n    }\n\n    let exe = std::env::current_exe().expect(\"current exe\");\n    let status = Command::new(\"prlimit\")\n        .args([\n            \"--as=134217728\",\n            \"--\",\n            exe.to_str().expect(\"utf8 exe path\"),\n            \"--exact\",\n            \"compression::tests::remote_compressed_payload_can_crash_under_memory_limit\",\n            \"--nocapture\",\n        ])\n        .env(CHILD_ENV, \"1\")\n        .status()\n        .expect(\"spawn child\");\n\n    assert!(\n        !status.success(),\n        \"expected child to fail under constrained address space\"\n    );\n}\n```\n\nOn that historical worktree, the constrained-memory child aborts in the old Unix `CryptoVec` path with:\n\n```text\nunsafe precondition(s) violated: NonNull::new_unchecked requires that the pointer is non-null\nthread caused non-unwinding panic. aborting.\n```\n\nTo run the reproduced checks:\n\n```bash\ncargo test -p russh oversized_agent_response_is_rejected_before_allocation -- --nocapture\ncargo test -p russh oversized_agent_request_is_rejected_before_allocation -- --nocapture\ncargo test -p russh-cryptovec\n```\n\nHistorical pre-`0.58.0` checks were run from the detached `91d431d` worktree with:\n\n```bash\ncargo test --offline -p russh remote_packet_length_grows_transport_cryptovec_buffer -- --nocapture\ncargo test --offline -p russh remote_compressed_payload_expands_cryptovec_output -- --nocapture\ncargo test --offline -p russh remote_compressed_payload_can_crash_under_memory_limit -- --nocapture\n```\n\n### Impact\nThis is a memory-safety hardening issue with demonstrated untrusted-input reachability.\n\nWhat is demonstrated:\n\n- current local agent peers could previously reach allocation growth directly from attacker-controlled frame lengths\n- historical remote SSH traffic could previously reach `CryptoVec` through transport and compression buffers in `russh \u003c 0.58.0`\n- under constrained memory, the historical remote compression path can be turned into a process abort in the old Unix `CryptoVec` code\n- the fixed code now rejects oversized agent frames early and hardens the underlying allocation paths\n\nWhat is not demonstrated:\n\n- practical code execution\n- a demonstrated integrity or confidentiality break",
  "id": "GHSA-g9f8-wqj9-fjw5",
  "modified": "2026-06-11T14:06:39Z",
  "published": "2026-05-21T20:49:07Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Eugeny/russh/security/advisories/GHSA-g9f8-wqj9-fjw5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46673"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Eugeny/russh"
    },
    {
      "type": "WEB",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0153.html"
    },
    {
      "type": "WEB",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0154.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Russh: Unchecked CryptoVec allocation and growth handling is reachable"
}

Mitigation

Requirements

Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.

Mitigation

Architecture and Design

Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.

Mitigation

Architecture and Design

Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place, and it will help the administrator to identify who is committing the abuse. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.

Mitigation MIT-5

Implementation

Strategy: Input Validation

Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

Mitigation MIT-15

Architecture and Design

For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Mitigation

Architecture and Design

Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution can be difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply requires more resources on the part of the attacker.
recognizes the attack and denies that user further access for a given amount of time, typically by using increasing time delays
uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed.

Mitigation

Architecture and Design

Ensure that protocols have specific limits of scale placed on them.

Mitigation MIT-38.1

Architecture and Design Implementation

If the program must fail, ensure that it fails gracefully (fails closed). There may be a temptation to simply let the program fail poorly in cases such as low memory conditions, but an attacker may be able to assert control before the software has fully exited. Alternately, an uncontrolled failure could cause cascading problems with other downstream components; for example, the program could send a signal to a downstream process so the process immediately knows that a problem has occurred and has a better chance of recovery.
Ensure that all failures in resource allocation place the system into a safe posture.

Mitigation MIT-47

Operation Architecture and Design

Strategy: Resource Limitation

Use quotas or other resource-limiting settings provided by the operating system or environment. For example, when managing system resources in POSIX, setrlimit() can be used to set limits for certain types of resources, and getrlimit() can determine how many resources are available. However, these functions are not available on all operating systems.
When the current levels get close to the maximum that is defined for the application (see CWE-770), then limit the allocation of further resources to privileged users; alternately, begin releasing resources for less-privileged users. While this mitigation may protect the system from attack, it will not necessarily stop attackers from adversely impacting other users.
Ensure that the application performs the appropriate error checks and error handling in case resources become unavailable (CWE-703).

CAPEC-125: Flooding

An adversary consumes the resources of a target by rapidly engaging in a large number of interactions with the target. This type of attack generally exposes a weakness in rate limiting or flow. When successful this attack prevents legitimate users from accessing the service and can cause the target to crash. This attack differs from resource depletion through leaks or allocations in that the latter attacks do not rely on the volume of requests made to the target but instead focus on manipulation of the target's operations. The key factor in a flooding attack is the number of requests the adversary can make in a given period of time. The greater this number, the more likely an attack is to succeed against a given target.

CAPEC-130: Excessive Allocation

An adversary causes the target to allocate excessive resources to servicing the attackers' request, thereby reducing the resources available for legitimate services and degrading or denying services. Usually, this attack focuses on memory allocation, but any finite resource on the target could be the attacked, including bandwidth, processing cycles, or other resources. This attack does not attempt to force this allocation through a large number of requests (that would be Resource Depletion through Flooding) but instead uses one or a small number of requests that are carefully formatted to force the target to allocate excessive resources to service this request(s). Often this attack takes advantage of a bug in the target to cause the target to allocate resources vastly beyond what would be needed for a normal request.

CAPEC-147: XML Ping of the Death

An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.

CAPEC-197: Exponential Data Expansion

An adversary submits data to a target application which contains nested exponential data expansion to produce excessively large output. Many data format languages allow the definition of macro-like structures that can be used to simplify the creation of complex structures. However, this capability can be abused to create excessive demands on a processor's CPU and memory. A small number of nested expansions can result in an exponential growth in demands on memory.

CAPEC-229: Serialized Data Parameter Blowup

This attack exploits certain serialized data parsers (e.g., XML, YAML, etc.) which manage data in an inefficient manner. The attacker crafts an serialized data file with multiple configuration parameters in the same dataset. In a vulnerable parser, this results in a denial of service condition where CPU resources are exhausted because of the parsing algorithm. The weakness being exploited is tied to parser implementation and not language specific.

CAPEC-230: Serialized Data with Nested Payloads

Applications often need to transform data in and out of a data format (e.g., XML and YAML) by using a parser. It may be possible for an adversary to inject data that may have an adverse effect on the parser when it is being processed. Many data format languages allow the definition of macro-like structures that can be used to simplify the creation of complex structures. By nesting these structures, causing the data to be repeatedly substituted, an adversary can cause the parser to consume more resources while processing, causing excessive memory consumption and CPU utilization.

CAPEC-231: Oversized Serialized Data Payloads

An adversary injects oversized serialized data payloads into a parser during data processing to produce adverse effects upon the parser such as exhausting system resources and arbitrary code execution.

CAPEC-469: HTTP DoS

An attacker performs flooding at the HTTP level to bring down only a particular web application rather than anything listening on a TCP/IP connection. This denial of service attack requires substantially fewer packets to be sent which makes DoS harder to detect. This is an equivalent of SYN flood in HTTP. The idea is to keep the HTTP session alive indefinitely and then repeat that hundreds of times. This attack targets resource depletion weaknesses in web server software. The web server will wait to attacker's responses on the initiated HTTP sessions while the connection threads are being exhausted.

CAPEC-482: TCP Flood

An adversary may execute a flooding attack using the TCP protocol with the intent to deny legitimate users access to a service. These attacks exploit the weakness within the TCP protocol where there is some state information for the connection the server needs to maintain. This often involves the use of TCP SYN messages.

CAPEC-486: UDP Flood

An adversary may execute a flooding attack using the UDP protocol with the intent to deny legitimate users access to a service by consuming the available network bandwidth. Additionally, firewalls often open a port for each UDP connection destined for a service with an open UDP port, meaning the firewalls in essence save the connection state thus the high packet nature of a UDP flood can also overwhelm resources allocated to the firewall. UDP attacks can also target services like DNS or VoIP which utilize these protocols. Additionally, due to the session-less nature of the UDP protocol, the source of a packet is easily spoofed making it difficult to find the source of the attack.

CAPEC-487: ICMP Flood

An adversary may execute a flooding attack using the ICMP protocol with the intent to deny legitimate users access to a service by consuming the available network bandwidth. A typical attack involves a victim server receiving ICMP packets at a high rate from a wide range of source addresses. Additionally, due to the session-less nature of the ICMP protocol, the source of a packet is easily spoofed making it difficult to find the source of the attack.

CAPEC-488: HTTP Flood

An adversary may execute a flooding attack using the HTTP protocol with the intent to deny legitimate users access to a service by consuming resources at the application layer such as web services and their infrastructure. These attacks use legitimate session-based HTTP GET requests designed to consume large amounts of a server's resources. Since these are legitimate sessions this attack is very difficult to detect.

CAPEC-489: SSL Flood

An adversary may execute a flooding attack using the SSL protocol with the intent to deny legitimate users access to a service by consuming all the available resources on the server side. These attacks take advantage of the asymmetric relationship between the processing power used by the client and the processing power used by the server to create a secure connection. In this manner the attacker can make a large number of HTTPS requests on a low provisioned machine to tie up a disproportionately large number of resources on the server. The clients then continue to keep renegotiating the SSL connection. When multiplied by a large number of attacking machines, this attack can result in a crash or loss of service to legitimate users.

CAPEC-490: Amplification

An adversary may execute an amplification where the size of a response is far greater than that of the request that generates it. The goal of this attack is to use a relatively few resources to create a large amount of traffic against a target server. To execute this attack, an adversary send a request to a 3rd party service, spoofing the source address to be that of the target server. The larger response that is generated by the 3rd party service is then sent to the target server. By sending a large number of initial requests, the adversary can generate a tremendous amount of traffic directed at the target. The greater the discrepancy in size between the initial request and the final payload delivered to the target increased the effectiveness of this attack.

CAPEC-491: Quadratic Data Expansion

An adversary exploits macro-like substitution to cause a denial of service situation due to excessive memory being allocated to fully expand the data. The result of this denial of service could cause the application to freeze or crash. This involves defining a very large entity and using it multiple times in a single entity substitution. CAPEC-197 is a similar attack pattern, but it is easier to discover and defend against. This attack pattern does not perform multi-level substitution and therefore does not obviously appear to consume extensive resources.

CAPEC-493: SOAP Array Blowup

An adversary may execute an attack on a web service that uses SOAP messages in communication. By sending a very large SOAP array declaration to the web service, the attacker forces the web service to allocate space for the array elements before they are parsed by the XML parser. The attacker message is typically small in size containing a large array declaration of say 1,000,000 elements and a couple of array elements. This attack targets exhaustion of the memory resources of the web service.

CAPEC-494: TCP Fragmentation

An adversary may execute a TCP Fragmentation attack against a target with the intention of avoiding filtering rules of network controls, by attempting to fragment the TCP packet such that the headers flag field is pushed into the second fragment which typically is not filtered.

CAPEC-495: UDP Fragmentation

An attacker may execute a UDP Fragmentation attack against a target server in an attempt to consume resources such as bandwidth and CPU. IP fragmentation occurs when an IP datagram is larger than the MTU of the route the datagram has to traverse. Typically the attacker will use large UDP packets over 1500 bytes of data which forces fragmentation as ethernet MTU is 1500 bytes. This attack is a variation on a typical UDP flood but it enables more network bandwidth to be consumed with fewer packets. Additionally it has the potential to consume server CPU resources and fill memory buffers associated with the processing and reassembling of fragmented packets.

CAPEC-496: ICMP Fragmentation

An attacker may execute a ICMP Fragmentation attack against a target with the intention of consuming resources or causing a crash. The attacker crafts a large number of identical fragmented IP packets containing a portion of a fragmented ICMP message. The attacker these sends these messages to a target host which causes the host to become non-responsive. Another vector may be sending a fragmented ICMP message to a target host with incorrect sizes in the header which causes the host to hang.

CAPEC-528: XML Flood

An adversary may execute a flooding attack using XML messages with the intent to deny legitimate users access to a web service. These attacks are accomplished by sending a large number of XML based requests and letting the service attempt to parse each one. In many cases this type of an attack will result in a XML Denial of Service (XDoS) due to an application becoming unstable, freezing, or crashing.

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