CVE-2026-121437Mistune 3.3.0 before 3.3.4 Quadratic-Time DoS via _process_emphasis_delimiters

Beschreibung

Mistune from 3.3.0 before 3.3.4 contains a denial of service vulnerability that allows remote attackers to exhaust CPU through quadratic-time emphasis delimiter processing. Attackers can submit small markdown documents with repeated patterns like "*a_b" to trigger an O(n²) index-fixup loop, stalling workers for seconds.

Daten: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Wiedergegeben wie in der Quelle, auf Englisch.

Betroffene Produkte und Versionen

Referenzen und Patches

• GitHub Security Advisory (GHSA-qp42-r9j6-83g9) vendor-advisory
• Patch Commit patch
• VulnCheck Advisory: Mistune 3.3.0 before 3.3.4 Quadratic-Time DoS via _process_emphasis_delimiters third-party-advisory