Common Weakness Enumeration

CWE-1333

Allowed

Inefficient Regular Expression Complexity

Abstraction: Base · Status: Draft

API response cwe.mitre.org

The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

724 vulnerabilities reference this CWE, most recent first.

GHSA-HX9M-JF43-8FFR

Vulnerability from github – Published: 2026-01-21 16:57 – Updated: 2026-05-20 00:53
VLAI
Summary
seroval affected by Denial of Service via RegExp serialization
Details

Overriding RegExp serialization with extremely large patterns can exhaust JavaScript runtime memory during deserialization. Additionally, overriding RegExp serialization with patterns that trigger catastrophic backtracking can lead to ReDoS (Regular Expression Denial of Service).

Mitigation:
Seroval introduces disabledFeatures (a bitmask) in serialization/deserialization methods, with Feature.RegExp as a dedicated flag. Users are recommended to configure disabledFeatures to disable RegExp serialization entirely.

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= 1.4.0"
      },
      "package": {
        "ecosystem": "npm",
        "name": "seroval"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.2.0"
            },
            {
              "fixed": "1.4.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-23956"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-21T16:57:06Z",
    "nvd_published_at": "2026-01-22T02:15:52Z",
    "severity": "HIGH"
  },
  "details": "Overriding RegExp serialization with extremely large patterns can **exhaust JavaScript runtime memory** during deserialization. Additionally, overriding RegExp serialization with patterns that trigger **catastrophic backtracking** can lead to ReDoS (Regular Expression Denial of Service).  \n\n**Mitigation**:  \n`Seroval` introduces `disabledFeatures` (a bitmask) in serialization/deserialization methods, with `Feature.RegExp` as a dedicated flag. **Users are recommended to configure `disabledFeatures` to disable RegExp serialization entirely.**",
  "id": "GHSA-hx9m-jf43-8ffr",
  "modified": "2026-05-20T00:53:27Z",
  "published": "2026-01-21T16:57:06Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/lxsmnsyc/seroval/security/advisories/GHSA-hx9m-jf43-8ffr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23956"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lxsmnsyc/seroval/commit/ce9408ebc87312fcad345a73c172212f2a798060"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/lxsmnsyc/seroval"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lxsmnsyc/seroval/blob/v0.2.0/packages/seroval/src/index.ts#L90"
    }
  ],
  "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": "seroval affected by Denial of Service via RegExp serialization"
}

GHSA-HXC7-QJFV-5432

Vulnerability from github – Published: 2022-10-17 19:00 – Updated: 2022-10-19 19:00
VLAI
Details

A potential DoS vulnerability was discovered in Gitlab CE/EE versions starting from 10.7 before 15.1.5, all versions starting from 15.2 before 15.2.3, all versions starting from 15.3 before 15.3.1 allowed an attacker to trigger high CPU usage via a special crafted input added in the Commit message field.

Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2022-2908"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333",
      "CWE-400"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-10-17T16:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A potential DoS vulnerability was discovered in Gitlab CE/EE versions starting from 10.7 before 15.1.5, all versions starting from 15.2 before 15.2.3, all versions starting from 15.3 before 15.3.1 allowed an attacker to trigger high CPU usage via a special crafted input added in the Commit message field.",
  "id": "GHSA-hxc7-qjfv-5432",
  "modified": "2022-10-19T19:00:19Z",
  "published": "2022-10-17T19:00:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-2908"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/1584156"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/cves/-/blob/master/2022/CVE-2022-2908.json"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/gitlab/-/issues/363734"
    }
  ],
  "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:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-HXQX-XWVH-44M2

Vulnerability from github – Published: 2022-05-27 16:36 – Updated: 2023-08-28 13:59
VLAI
Summary
Denial of Service Vulnerability in Rack Multipart Parsing
Details

There is a possible denial of service vulnerability in the multipart parsing component of Rack. This vulnerability has been assigned the CVE identifier CVE-2022-30122.

Versions Affected: >= 1.2 Not affected: < 1.2 Fixed Versions: 2.0.9.1, 2.1.4.1, 2.2.3.1

Impact

Carefully crafted multipart POST requests can cause Rack's multipart parser to take much longer than expected, leading to a possible denial of service vulnerability.

Impacted code will use Rack's multipart parser to parse multipart posts. This includes directly using the multipart parser like this:

params = Rack::Multipart.parse_multipart(env)

But it also includes reading POST data from a Rack request object like this:

p request.POST # read POST data
p request.params # reads both query params and POST data

All users running an affected release should either upgrade or use one of the workarounds immediately.

Workarounds

There are no feasible workarounds for this issue.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.0.9.0"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "rack"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.2"
            },
            {
              "fixed": "2.0.9.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.1.4.0"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "rack"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.1"
            },
            {
              "fixed": "2.1.4.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.2.3.0"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "rack"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.2"
            },
            {
              "fixed": "2.2.3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-30122"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333",
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-05-27T16:36:52Z",
    "nvd_published_at": "2022-12-05T22:15:00Z",
    "severity": "HIGH"
  },
  "details": "There is a possible denial of service vulnerability in the multipart parsing component of Rack.  This vulnerability has been assigned the CVE identifier CVE-2022-30122.\n\nVersions Affected:  \u003e= 1.2\nNot affected:       \u003c 1.2\nFixed Versions:     2.0.9.1, 2.1.4.1, 2.2.3.1\n\n## Impact\nCarefully crafted multipart POST requests can cause Rack\u0027s multipart parser to take much longer than expected, leading to a possible denial of service vulnerability.\n\nImpacted code will use Rack\u0027s multipart parser to parse multipart posts.  This includes directly using the multipart parser like this:\n\n```\nparams = Rack::Multipart.parse_multipart(env)\n```\n\nBut it also includes reading POST data from a Rack request object like this:\n\n```\np request.POST # read POST data\np request.params # reads both query params and POST data\n```\n\nAll users running an affected release should either upgrade or use one of the workarounds immediately.\n\n## Workarounds\nThere are no feasible workarounds for this issue.\n",
  "id": "GHSA-hxqx-xwvh-44m2",
  "modified": "2023-08-28T13:59:06Z",
  "published": "2022-05-27T16:36:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-30122"
    },
    {
      "type": "WEB",
      "url": "https://discuss.rubyonrails.org/t/cve-2022-30122-denial-of-service-vulnerability-in-rack-multipart-parsing/80729"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rack/rack"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/rack/CVE-2022-30122.yml"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/ruby-security-ann/c/L2Axto442qk"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202310-18"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20231208-0012"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2023/dsa-5530"
    }
  ],
  "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": "Denial of Service Vulnerability in Rack Multipart Parsing"
}

GHSA-J3Q9-MXJG-W52F

Vulnerability from github – Published: 2026-03-27 22:23 – Updated: 2026-03-27 22:23
VLAI
Summary
path-to-regexp vulnerable to Denial of Service via sequential optional groups
Details

Impact

A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as {a}{b}{c}:z. The generated regex grows exponentially with the number of groups, causing denial of service.

Patches

Fixed in version 8.4.0.

Workarounds

Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "path-to-regexp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0"
            },
            {
              "fixed": "8.4.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-4926"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333",
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-27T22:23:27Z",
    "nvd_published_at": "2026-03-26T19:17:08Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nA bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service.\n\n### Patches\n\nFixed in version 8.4.0.\n\n### Workarounds\n\nLimit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.",
  "id": "GHSA-j3q9-mxjg-w52f",
  "modified": "2026-03-27T22:23:27Z",
  "published": "2026-03-27T22:23:27Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pillarjs/path-to-regexp/security/advisories/GHSA-j3q9-mxjg-w52f"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-4926"
    },
    {
      "type": "WEB",
      "url": "https://cna.openjsf.org/security-advisories.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pillarjs/path-to-regexp"
    }
  ],
  "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": "path-to-regexp vulnerable to Denial of Service via sequential optional groups"
}

GHSA-J3X3-R585-4QHG

Vulnerability from github – Published: 2024-11-25 09:30 – Updated: 2024-11-25 18:29
VLAI
Summary
Duplicate Advisory: org.keycloak:keycloak-services has Inefficient Regular Expression Complexity
Details

Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-wq8x-cg39-8mrr. This link is maintained to preserve external references.

Original Description

A vulnerability was found in the Keycloak-services package. If untrusted data is passed to the SearchQueryUtils method, it could lead to a denial of service (DoS) scenario by exhausting system resources due to a Regex complexity.

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.keycloak:keycloak-services"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "24.0.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.keycloak:keycloak-services"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "25.0.0"
            },
            {
              "fixed": "26.0.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-11-25T18:29:52Z",
    "nvd_published_at": "2024-11-25T08:15:03Z",
    "severity": "MODERATE"
  },
  "details": "## Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-wq8x-cg39-8mrr. This link is maintained to preserve external references.\n\n## Original Description\nA vulnerability was found in the Keycloak-services package. If untrusted data is passed to the SearchQueryUtils method, it could lead to a denial of service (DoS) scenario by exhausting system resources due to a Regex complexity.",
  "id": "GHSA-j3x3-r585-4qhg",
  "modified": "2024-11-25T18:29:52Z",
  "published": "2024-11-25T09:30:58Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-10270"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2024:10175"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2024:10176"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2024:10177"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2024:10178"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2024-10270"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2321214"
    }
  ],
  "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": "Duplicate Advisory: org.keycloak:keycloak-services has Inefficient Regular Expression Complexity",
  "withdrawn": "2024-11-25T18:29:52Z"
}

GHSA-J47Q-RC62-W448

Vulnerability from github – Published: 2025-07-07 23:36 – Updated: 2025-12-31 22:50
VLAI
Summary
fastapi-guard is vulnerable to ReDoS through inefficient regex
Details

Summary

fastapi-guard detects penetration attempts by using regex patterns to scan incoming requests. However, some of the regex patterns used in detection are extremely inefficient and can cause polynomial complexity backtracks when handling specially crafted inputs.

It is not as severe as exponential complexity ReDoS, but still downgrades performance and allows DoS exploits. An attacker can trigger high cpu usage and make a service unresponsive for hours by sending a single request in size of KBs.

PoC

e.g. https://github.com/rennf93/fastapi-guard/blob/1e6c2873bfc7866adcbe5fc4da72f2d79ea552e7/guard/handlers/suspatterns_handler.py#L31C79-L32C7

payload = lambda n: '<'*n+ ' '*n+ 'style=' + '"'*n + ' '*n+ 'url('*n # complexity: O(n^5)

print(requests.post("http://172.24.1.3:8000/", data=payload(50)).elapsed) # 0:00:03.771120
print(requests.post("http://172.24.1.3:8000/", data=payload(100)).elapsed) # 0:01:17.952637
print(requests.post("http://172.24.1.3:8000/", data=payload(200)).elapsed) # timeout (>15min)

Single-threaded uvicorn workers can not handle any other concurrent requests during the elapsed time.

Impact

Penetration detection is enabled by default. Services that use fastapi-guard middleware without explicitly setting enable_penetration_detection=False are vulnerable to DoS.

Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 3.0.0"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "fastapi-guard"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-53539"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-07-07T23:36:39Z",
    "nvd_published_at": "2025-07-07T20:15:28Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nfastapi-guard detects penetration attempts by using regex patterns to scan incoming requests. However, some of the regex patterns used in detection are extremely inefficient and can cause polynomial complexity backtracks when handling specially crafted inputs.\n\nIt is not as severe as _exponential_ complexity ReDoS, but still downgrades performance and allows DoS exploits. An attacker can trigger high cpu usage and make a service unresponsive for hours by sending a single request in size of KBs.\n\n### PoC\n\ne.g. https://github.com/rennf93/fastapi-guard/blob/1e6c2873bfc7866adcbe5fc4da72f2d79ea552e7/guard/handlers/suspatterns_handler.py#L31C79-L32C7\n\n```python\npayload = lambda n: \u0027\u003c\u0027*n+ \u0027 \u0027*n+ \u0027style=\u0027 + \u0027\"\u0027*n + \u0027 \u0027*n+ \u0027url(\u0027*n # complexity: O(n^5)\n\nprint(requests.post(\"http://172.24.1.3:8000/\", data=payload(50)).elapsed) # 0:00:03.771120\nprint(requests.post(\"http://172.24.1.3:8000/\", data=payload(100)).elapsed) # 0:01:17.952637\nprint(requests.post(\"http://172.24.1.3:8000/\", data=payload(200)).elapsed) # timeout (\u003e15min)\n```\n\nSingle-threaded uvicorn workers can not handle any other concurrent requests during the elapsed time.\n\n### Impact\n\nPenetration detection is enabled by default. Services that use fastapi-guard middleware without explicitly setting `enable_penetration_detection=False` are vulnerable to DoS.",
  "id": "GHSA-j47q-rc62-w448",
  "modified": "2025-12-31T22:50:34Z",
  "published": "2025-07-07T23:36:39Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/rennf93/fastapi-guard/security/advisories/GHSA-j47q-rc62-w448"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-53539"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rennf93/fastapi-guard/commit/d9d50e8130b7b434cdc1b001b8cfd03a06729f7f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rennf93/fastapi-guard"
    }
  ],
  "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:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "fastapi-guard is vulnerable to ReDoS through inefficient regex"
}

GHSA-J533-2G8V-PMPG

Vulnerability from github – Published: 2023-02-12 15:30 – Updated: 2023-02-22 16:31
VLAI
Summary
Regular Expression Denial of Service in simple-markdown
Details

A vulnerability, which was classified as problematic, was found in simple-markdown 0.6.0. Affected is an unknown function of the file simple-markdown.js. The manipulation with the input <<<<<<<<<<:/:/:/:/:/:/:/:/:/:/ leads to inefficient regular expression complexity. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 0.6.1 is able to address this issue. The name of the patch is 015a719bf5cdc561feea05500ecb3274ef609cd2. It is recommended to upgrade the affected component. VDB-220638 is the identifier assigned to this vulnerability.

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": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "simple-markdown"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.6.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2019-25102"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-02-14T00:57:45Z",
    "nvd_published_at": "2023-02-12T14:15:00Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability, which was classified as problematic, was found in simple-markdown 0.6.0. Affected is an unknown function of the file simple-markdown.js. The manipulation with the input \u003c\u003c\u003c\u003c\u003c\u003c\u003c\u003c\u003c\u003c:/:/:/:/:/:/:/:/:/:/ leads to inefficient regular expression complexity. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 0.6.1 is able to address this issue. The name of the patch is 015a719bf5cdc561feea05500ecb3274ef609cd2. It is recommended to upgrade the affected component. VDB-220638 is the identifier assigned to this vulnerability.",
  "id": "GHSA-j533-2g8v-pmpg",
  "modified": "2023-02-22T16:31:59Z",
  "published": "2023-02-12T15:30:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-25102"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ariabuckles/simple-markdown/pull/73"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ariabuckles/simple-markdown/commit/015a719bf5cdc561feea05500ecb3274ef609cd2"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ariabuckles/simple-markdown"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ariabuckles/simple-markdown/releases/tag/0.6.1"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?ctiid.220638"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?id.220638"
    }
  ],
  "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": "Regular Expression Denial of Service in simple-markdown"
}

GHSA-J5CC-6RX8-FF96

Vulnerability from github – Published: 2025-06-17 15:31 – Updated: 2025-07-07 18:32
VLAI
Details

The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.

Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
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{
  "affected": [],
  "aliases": [
    "CVE-2025-6069"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-06-17T14:15:33Z",
    "severity": "MODERATE"
  },
  "details": "The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.",
  "id": "GHSA-j5cc-6rx8-ff96",
  "modified": "2025-07-07T18:32:21Z",
  "published": "2025-06-17T15:31:08Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-6069"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/issues/135462"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/pull/135464"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/4455cbabf991e202185a25a631af206f60bbc949"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/6eb6c5dbfb528bd07d77b60fd71fd05d81d45c41"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/8d1b3dfa09135affbbf27fb8babcf3c11415df49"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/ab0893fd5c579d9cea30841680e6d35fc478afb5"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/d851f8e258c7328814943e923a7df81bca15df4b"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/f3c6f882cddc8dc30320d2e73edf019e201394fc"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/fdc9d214c01cb4588f540cfa03726bbf2a33fc15"
    },
    {
      "type": "WEB",
      "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/K5PIYLR6EP3WR7ZOKKYQUWEDNQVUXOYM"
    }
  ],
  "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:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-J5P7-JF4Q-742Q

Vulnerability from github – Published: 2022-12-27 09:30 – Updated: 2023-01-10 15:38
VLAI
Summary
markdown-it vulnerable to Inefficient Regular Expression Complexity
Details

A vulnerability was found in markdown-it up to 2.x. It has been classified as problematic. Affected is an unknown function of the file lib/common/html_re.js. The manipulation leads to inefficient regular expression complexity. Upgrading to version 3.0.0 is able to address this issue. The name of the patch is 89c8620157d6e38f9872811620d25138fc9d1b0d. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-216852.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "markdown-it"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2015-10005"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-12-30T16:27:08Z",
    "nvd_published_at": "2022-12-27T09:15:00Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability was found in markdown-it up to 2.x. It has been classified as problematic. Affected is an unknown function of the file `lib/common/html_re.js`. The manipulation leads to inefficient regular expression complexity. Upgrading to version 3.0.0 is able to address this issue. The name of the patch is 89c8620157d6e38f9872811620d25138fc9d1b0d. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-216852.",
  "id": "GHSA-j5p7-jf4q-742q",
  "modified": "2023-01-10T15:38:01Z",
  "published": "2022-12-27T09:30:41Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2015-10005"
    },
    {
      "type": "WEB",
      "url": "https://github.com/markdown-it/markdown-it/commit/89c8620157d6e38f9872811620d25138fc9d1b0d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/markdown-it/markdown-it"
    },
    {
      "type": "WEB",
      "url": "https://github.com/markdown-it/markdown-it/releases/tag/3.0.0"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?ctiid.216852"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?id.216852"
    }
  ],
  "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": "markdown-it vulnerable to Inefficient Regular Expression Complexity"
}

GHSA-J6GC-792M-QGM2

Vulnerability from github – Published: 2023-01-18 18:23 – Updated: 2025-02-18 22:35
VLAI
Summary
ReDoS based DoS vulnerability in Active Support's underscore
Details

There is a possible regular expression based DoS vulnerability in Active Support. This vulnerability has been assigned the CVE identifier CVE-2023-22796.

Versions Affected: All Not affected: None Fixed Versions: 5.2.8.15 (Rails LTS, which is a paid service and not part of the rubygem), 6.1.7.1, 7.0.4.1 Impact

A specially crafted string passed to the underscore method can cause the regular expression engine to enter a state of catastrophic backtracking. This can cause the process to use large amounts of CPU and memory, leading to a possible DoS vulnerability.

This affects String#underscore, ActiveSupport::Inflector.underscore, String#titleize, and any other methods using these.

All users running an affected release should either upgrade or use one of the workarounds immediately. Releases

The FIXED releases are available at the normal locations. Workarounds

There are no feasible workarounds for this issue.

Users on Ruby 3.2.0 or greater may be able to reduce the impact by configuring Regexp.timeout. Patches

To aid users who aren’t able to upgrade immediately we have provided patches for the two supported release series. They are in git-am format and consist of a single changeset.

6-1-Avoid-regex-backtracking-in-Inflector.underscore.patch - Patch for 6.1 series
7-0-Avoid-regex-backtracking-in-Inflector.underscore.patch - Patch for 7.0 series

Please note that only the 7.0.Z and 6.1.Z series are supported at present, and 6.0.Z for severe vulnerabilities. Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases.

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{
  "affected": [
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "activesupport"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.7.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "activesupport"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.0.4.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-22796"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-01-18T18:23:20Z",
    "nvd_published_at": "2023-02-09T20:15:00Z",
    "severity": "LOW"
  },
  "details": "There is a possible regular expression based DoS vulnerability in Active Support. This vulnerability has been assigned the CVE identifier CVE-2023-22796.\n\nVersions Affected: All Not affected: None Fixed Versions: 5.2.8.15 (Rails LTS, which is a paid service and not part of the rubygem), 6.1.7.1, 7.0.4.1\nImpact\n\nA specially crafted string passed to the underscore method can cause the regular expression engine to enter a state of catastrophic backtracking. This can cause the process to use large amounts of CPU and memory, leading to a possible DoS vulnerability.\n\nThis affects String#underscore, ActiveSupport::Inflector.underscore, String#titleize, and any other methods using these.\n\nAll users running an affected release should either upgrade or use one of the workarounds immediately.\nReleases\n\nThe FIXED releases are available at the normal locations.\nWorkarounds\n\nThere are no feasible workarounds for this issue.\n\nUsers on Ruby 3.2.0 or greater may be able to reduce the impact by configuring Regexp.timeout.\nPatches\n\nTo aid users who aren\u2019t able to upgrade immediately we have provided patches for the two supported release series. They are in git-am format and consist of a single changeset.\n\n    6-1-Avoid-regex-backtracking-in-Inflector.underscore.patch - Patch for 6.1 series\n    7-0-Avoid-regex-backtracking-in-Inflector.underscore.patch - Patch for 7.0 series\n\nPlease note that only the 7.0.Z and 6.1.Z series are supported at present, and 6.0.Z for severe vulnerabilities. Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases.",
  "id": "GHSA-j6gc-792m-qgm2",
  "modified": "2025-02-18T22:35:59Z",
  "published": "2023-01-18T18:23:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-22796"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/commit/2164d4f6a1bde74b911fe9ba3c8df1b5bf345bf8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/commit/a7cda7e6aa5334ab41b1f4b0f671be931be946ef"
    },
    {
      "type": "WEB",
      "url": "https://discuss.rubyonrails.org/t/cve-2023-22796-possible-redos-based-dos-vulnerability-in-active-supports-underscore/82116"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rails/rails"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/releases/tag/v6.1.7.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/releases/tag/v7.0.4.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/activesupport/CVE-2023-22796.yml"
    },
    {
      "type": "WEB",
      "url": "https://rubyonrails.org/2023/1/17/Rails-Versions-6-0-6-1-6-1-7-1-7-0-4-1-have-been-released"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [],
  "summary": "ReDoS based DoS vulnerability in Active Support\u0027s underscore"
}
Mitigation
Architecture and Design

Use regular expressions that do not support backtracking, e.g. by removing nested quantifiers.

Mitigation
System Configuration

Set backtracking limits in the configuration of the regular expression implementation, such as PHP's pcre.backtrack_limit. Also consider limits on execution time for the process.

Mitigation
Implementation

Do not use regular expressions with untrusted input. If regular expressions must be used, avoid using backtracking in the expression.

Mitigation
Implementation

Limit the length of the input that the regular expression will process.

CAPEC-492: Regular Expression Exponential Blowup

An adversary may execute an attack on a program that uses a poor Regular Expression(Regex) implementation by choosing input that results in an extreme situation for the Regex. A typical extreme situation operates at exponential time compared to the input size. This is due to most implementations using a Nondeterministic Finite Automaton(NFA) state machine to be built by the Regex algorithm since NFA allows backtracking and thus more complex regular expressions.

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