CVE-2026-59887

HIGH7.5

linkify-it: Quadratic-complexity DoS via the `mailto:` validator scan-loop on attacker text

Published Jul 8, 2026

Modified 1 months ago

Details

linkify-it is a links recognition library with full Unicode support. Prior to 5.0.2, the mailto: schema validator used by .test() and .match() can be invoked at every mailto: occurrence and scan the remaining input through src_email_name in lib/re.mjs, causing O(n^2) CPU consumption on crafted user text. This issue is fixed in version 5.0.2.

References

WEB

https://github.com/markdown-it/linkify-it/commit/105e5d77f7d119871d2b2d86ed208568eb3e7ffe

WEB

https://github.com/markdown-it/linkify-it/releases/tag/5.0.2

WEB

https://github.com/markdown-it/linkify-it/security/advisories/GHSA-v245-v573-v5vm

ADVISORY

https://www.cve.org/CVERecord?id=CVE-2026-59887

CVSS Analysis

CVSS v3.1

7.5