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Status published
Critical
CVE-2025-25200
Koa has Inefficient Regular Expression Complexity
Vulnerability 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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
- https://github.com/koajs/koa/security/advisories/GHSA-593f-38f6-jp5m
- https://github.com/koajs/koa/commit/5054af6e31ffd451a4151a1fe144cef6e5d0d83c
- https://github.com/koajs/koa/commit/5f294bb1c7c8d9c61904378d250439a321bffd32
- https://github.com/koajs/koa/commit/93fe903fc966635a991bcf890cfc3427d33a1a08
- https://github.com/koajs/koa/blob/master/lib/request.js#L259
- https://github.com/koajs/koa/blob/master/lib/request.js#L404
- https://github.com/koajs/koa/releases/tag/2.15.4
Affected Vendor
koajs
View all reports →Affected Software
koa
Vulnerable Versions:
< 0.21.2, >= 1.0.0, < 1.7.1, >= 2.0.0-alpha.1, < 2.15.4, >= 3.0.0-alpha.0, < < 3.0.0-alpha.3
Timeline
Official Publish:
February 12th, 2025
Last Modified:
February 12th, 2025
Added to House:
July 22nd, 2026