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GHSA-593F-38F6-JP5M

Vulnerability from github – Published: 2025-02-12 19:23 – Updated: 2025-02-12 19:23
VLAI
Summary
Inefficient Regular Expression Complexity in koa
Details

Summary

Koa uses an evil regex to parse the X-Forwarded-Proto and X-Forwarded-Host HTTP headers. This can be exploited to carry out a Denial-of-Service attack.

PoC

Coming soon.

Impact

This is a Regex Denial-of-Service attack and causes memory exhaustion. The regex should be improved and empty values should not be allowed.

Severity
9.2 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "koa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0.0"
            },
            {
              "fixed": "2.15.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "koa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0-alpha.0"
            },
            {
              "fixed": "3.0.0-alpha.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "koa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.0.0"
            },
            {
              "fixed": "1.7.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "koa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.21.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-25200"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-02-12T19:23:09Z",
    "nvd_published_at": "2025-02-12T18:15:28Z",
    "severity": "CRITICAL"
  },
  "details": "### Summary\nKoa uses an evil regex to parse the `X-Forwarded-Proto` and `X-Forwarded-Host` HTTP headers. This can be exploited to carry out a Denial-of-Service attack.\n\n### PoC\n\nComing soon.\n\n### Impact\nThis is a Regex Denial-of-Service attack and causes memory exhaustion. The regex should be improved and empty values should not be allowed.",
  "id": "GHSA-593f-38f6-jp5m",
  "modified": "2025-02-12T19:23:09Z",
  "published": "2025-02-12T19:23:09Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/koajs/koa/security/advisories/GHSA-593f-38f6-jp5m"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-25200"
    },
    {
      "type": "WEB",
      "url": "https://github.com/koajs/koa/commit/5054af6e31ffd451a4151a1fe144cef6e5d0d83c"
    },
    {
      "type": "WEB",
      "url": "https://github.com/koajs/koa/commit/5f294bb1c7c8d9c61904378d250439a321bffd32"
    },
    {
      "type": "WEB",
      "url": "https://github.com/koajs/koa/commit/93fe903fc966635a991bcf890cfc3427d33a1a08"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/koajs/koa"
    },
    {
      "type": "WEB",
      "url": "https://github.com/koajs/koa/releases/tag/2.15.4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Inefficient Regular Expression Complexity in koa"
}



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