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.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenCVSS 8.7NVD modified 2026-10-20 02:17
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 7
- https://gist.github.com/R3tro16/92948206e9893a3739b91746439384ab
- https://gist.github.com/mmadersbacher/46050b4224eb979431986cdef1dd2ad3
- https://github.com/alexcorvi/anchorme.js
- https://github.com/alexcorvi/anchorme.js/blob/f3ae9850baa344f27b46bb149e9b891831d273b1/src/index.ts#L109
- https://www.npmjs.com/package/anchorme
- https://www.vulncheck.com/advisories/anchorme-through-3.0.8-regular-expression-denial-of-service
- https://gist.github.com/mmadersbacher/46050b4224eb979431986cdef1dd2ad3