Vulnerability in alexcorvi anchorme

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official description

anchorme through 3.0.8 contains a regular expression denial of service vulnerability in the IPv6 host extraction regex due to catastrophic backtracking. Attackers can supply specially crafted input strings with repeated patterns to cause exponential regex engine backtracking, blocking the Node.js event loop and denying service to other requests.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• gist.github.com/R3tro16/92948206e9893a3739b91746439384ab
• gist.github.com/mmadersbacher/46050b4224eb979431986cdef1dd2ad3
• github.com/alexcorvi/anchorme.js
• github.com/alexcorvi/anchorme.js/blob/f3ae9850baa344f27b46bb149e9b891831d273b1/src/inde…
• www.npmjs.com/package/anchorme
• www.vulncheck.com/advisories/anchorme-through-3.0.8-regular-expression-denial-of-service