CVE-2025-25200

Koa has Inefficient Regular Expression Complexity

State
Published
Severity
9.2 Critical
Published
Feb 12, 2025
Updated
Feb 12, 2025
Reserved
Feb 3, 2025

Read the record on cve.org

Description

Koa is expressive middleware for Node.js using ES2017 async functions. Prior to versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3, 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. Versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3 fix the issue.

Scores

CVSSScoreVectorSource
4.09.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:HGitHub_M

Weaknesses

  • CWE-1333 Inefficient Regular Expression Complexity

Affected Products

ProductVersions
koakoajs
  • < 0.21.2Affected
  • >= 1.0.0, < 1.7.1Affected
  • >= 2.0.0-alpha.1, < 2.15.4Affected
  • >= 3.0.0-alpha.0, < < 3.0.0-alpha.3Affected

References

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