{"id":"CVE-2026-115352","title":"Mistune before 3.3.0 Quadratic-Time DoS via Unmatched Brackets in Inline Parser","summary":"Mistune before 3.3.0 contains an algorithmic complexity vulnerability in the inline link parser that allows unauthenticated attackers to exhaust CPU by submitting long runs of unmatched '[' characters. Attackers can send small markdown p…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-407"],"vendor":"lepture","product":"mistune","affected":["mistune < 3.3.0"],"published":"2026-10-22","updated":"2026-10-22","sourceUpdated":"2026-10-22T19:13:28.427Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-115352","references":[{"url":"https://github.com/lepture/mistune/security/advisories/GHSA-xrpv-r66x-8p7j","label":"GitHub Security Advisory (GHSA-xrpv-r66x-8p7j)"},{"url":"https://www.vulncheck.com/advisories/mistune-before-3.3.0-quadratic-time-dos-via-unmatched-brackets-in-inline-parser","label":"VulnCheck Advisory: Mistune before 3.3.0 Quadratic-Time DoS via Unmatched Brackets in Inline Parser"}],"tags":["cve.org"],"ingestedAt":"2026-10-22T22:00:50.396Z","slug":"CVE-2026-115352","body":"## Overview\n\nMistune before 3.3.0 contains an algorithmic complexity vulnerability in the inline link parser that allows unauthenticated attackers to exhaust CPU by submitting long runs of unmatched '[' characters. Attackers can send small markdown payloads that trigger O(N^2) parse_link_text and parse_link_label probing, occupying rendering workers for 30+ seconds per 16 KB input.\n\n## Affected\n\n- `mistune < 3.3.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}