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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.

673 vulnerabilities reference this CWE, most recent first.

GHSA-2FC8-VF8H-JFVW

Vulnerability from github – Published: 2026-09-14 21:31 – Updated: 2026-09-14 21:31
VLAI
Details

IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty are vulnerable to HTTP request smuggling, caused by improper parsing of the HTTP transfer-encoding request header. By sending a specially crafted HTTP transfer-encoding request header, an attacker could exploit this vulnerability to poison the web cache, bypass web application firewall protection, and conduct XSS attacks.

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": [],
  "aliases": [
    "CVE-2026-15396"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-14T20:16:38Z",
    "severity": "MODERATE"
  },
  "details": "IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty are vulnerable to HTTP request smuggling, caused by improper parsing of the HTTP transfer-encoding request header. By sending a specially crafted HTTP transfer-encoding request header, an attacker could exploit this vulnerability to poison the web cache, bypass web application firewall protection, and conduct XSS attacks.",
  "id": "GHSA-2fc8-vf8h-jfvw",
  "modified": "2026-09-14T21:31:43Z",
  "published": "2026-09-14T21:31:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-15396"
    },
    {
      "type": "WEB",
      "url": "https://www.ibm.com/support/pages/node/7286610"
    }
  ],
  "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"
    }
  ]
}

GHSA-2GCR-MFCQ-WCC3

Vulnerability from github – Published: 2026-06-04 18:01 – Updated: 2026-06-04 18:01
VLAI
Summary
Hono: app.mount() strips mount prefix using undecoded path, causing incorrect routing for percent-encoded paths
Details

Summary

app.mount() strips the mount prefix from the incoming request path using the raw URL pathname, while route matching is performed against the percent-decoded path. This inconsistency causes the prefix to be stripped at the wrong position when the path contains percent-encoded multi-byte characters, resulting in the mounted sub-application receiving an incorrect path.

Details

When app.mount(prefix, subApp) is called, Hono calculates the number of characters to strip based on the decoded mount prefix length, but then applies that slice to the raw URL pathname. When the URL contains percent-encoded characters that expand to fewer characters when decoded (such as encoded non-ASCII characters), the two representations have different lengths, so the prefix is stripped at the wrong byte offset.

As a result, the sub-application receives a path that does not correspond to the intended sub-path — it may receive a partial or garbled path instead of the expected value after the mount prefix is removed.

This issue arises when an application uses app.mount() with paths that contain percent-encoded characters, particularly when the mount prefix itself or the request path contains encoded non-ASCII characters.

Impact

A mounted sub-application may receive an incorrectly stripped path, causing requests to be routed to unintended handlers within the sub-application.

This may lead to:

  • Middleware or route handlers in the sub-application being bypassed or incorrectly matched due to the malformed path
  • Requests reaching sub-application routes that the developer did not intend to be accessible via the mounted path

This issue affects applications that use app.mount() where the request URL may contain percent-encoded characters in the mount prefix or subsequent path segments.

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": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "hono"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.12.21"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-47676"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444",
      "CWE-693"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-04T18:01:00Z",
    "nvd_published_at": "2026-05-28T17:16:32Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\n`app.mount()` strips the mount prefix from the incoming request path using the raw URL pathname, while route matching is performed against the percent-decoded path. This inconsistency causes the prefix to be stripped at the wrong position when the path contains percent-encoded multi-byte characters, resulting in the mounted sub-application receiving an incorrect path.\n\n### Details\n\nWhen `app.mount(prefix, subApp)` is called, Hono calculates the number of characters to strip based on the decoded mount prefix length, but then applies that slice to the raw URL pathname. When the URL contains percent-encoded characters that expand to fewer characters when decoded (such as encoded non-ASCII characters), the two representations have different lengths, so the prefix is stripped at the wrong byte offset.\n\nAs a result, the sub-application receives a path that does not correspond to the intended sub-path \u2014 it may receive a partial or garbled path instead of the expected value after the mount prefix is removed.\n\nThis issue arises when an application uses `app.mount()` with paths that contain percent-encoded characters, particularly when the mount prefix itself or the request path contains encoded non-ASCII characters.\n\n### Impact\n\nA mounted sub-application may receive an incorrectly stripped path, causing requests to be routed to unintended handlers within the sub-application.\n\nThis may lead to:\n\n- Middleware or route handlers in the sub-application being bypassed or incorrectly matched due to the malformed path\n- Requests reaching sub-application routes that the developer did not intend to be accessible via the mounted path\n\nThis issue affects applications that use `app.mount()` where the request URL may contain percent-encoded characters in the mount prefix or subsequent path segments.",
  "id": "GHSA-2gcr-mfcq-wcc3",
  "modified": "2026-06-04T18:01:00Z",
  "published": "2026-06-04T18:01:00Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/honojs/hono/security/advisories/GHSA-2gcr-mfcq-wcc3"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-47676"
    },
    {
      "type": "WEB",
      "url": "https://github.com/honojs/hono/commit/6cbb025ff87fca1a3d00d0ccca0eaf3a6385c3f1"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/honojs/hono"
    },
    {
      "type": "WEB",
      "url": "https://github.com/honojs/hono/releases/tag/v4.12.21"
    }
  ],
  "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"
    }
  ],
  "summary": "Hono: app.mount() strips mount prefix using undecoded path, causing incorrect routing for percent-encoded paths"
}

GHSA-2HWM-6XJF-3XMX

Vulnerability from github – Published: 2022-03-15 00:01 – Updated: 2022-03-19 00:01
VLAI
Details

Apache HTTP Server 2.4.52 and earlier fails to close inbound connection when errors are encountered discarding the request body, exposing the server to HTTP Request Smuggling

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-2022-22720"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-03-14T11:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Apache HTTP Server 2.4.52 and earlier fails to close inbound connection when errors are encountered discarding the request body, exposing the server to HTTP Request Smuggling",
  "id": "GHSA-2hwm-6xjf-3xmx",
  "modified": "2022-03-19T00:01:09Z",
  "published": "2022-03-15T00:01:02Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-22720"
    },
    {
      "type": "WEB",
      "url": "https://httpd.apache.org/security/vulnerabilities_24.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2022/03/msg00033.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RGWILBORT67SHMSLYSQZG2NMXGCMPUZO"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/X73C35MMMZGBVPQQCH7LQZUMYZNQA5FO"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/Z7H26WJ6TPKNWV3QKY4BHKUKQVUTZJTD"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202208-20"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20220321-0001"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/kb/HT213255"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/kb/HT213256"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/kb/HT213257"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpujul2022.html"
    },
    {
      "type": "WEB",
      "url": "http://seclists.org/fulldisclosure/2022/May/33"
    },
    {
      "type": "WEB",
      "url": "http://seclists.org/fulldisclosure/2022/May/35"
    },
    {
      "type": "WEB",
      "url": "http://seclists.org/fulldisclosure/2022/May/38"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2022/03/14/3"
    }
  ],
  "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-2M77-R9W3-W44V

Vulnerability from github – Published: 2026-04-24 00:31 – Updated: 2026-04-24 00:31
VLAI
Details

A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields. This allows an attacker to send HTTP requests containing multiple Content-Length headers with differing values.

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

{
  "affected": [],
  "aliases": [
    "CVE-2026-2708"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-23T22:16:29Z",
    "severity": "LOW"
  },
  "details": "A request smuggling vulnerability exists in libsoup\u0027s HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields. This allows an attacker to send HTTP requests containing multiple Content-Length headers with differing values.",
  "id": "GHSA-2m77-r9w3-w44v",
  "modified": "2026-04-24T00:31:51Z",
  "published": "2026-04-24T00:31:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-2708"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-2708"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2440743"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/500"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/513"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

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
Show details on source website
To clipboard 

{
  "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": []
}
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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