GHSA-296h-qmjr-9mv2MediumCVSS 5.3
Mistune before 3.3.3 contains a denial of service vulnerability in InlineParser.parse_link that...
🔗 CVE IDs covered (1)
📋 Description
Mistune before 3.3.3 contains a denial of service vulnerability in InlineParser.parse_link that allows attackers to cause quadratic CPU growth by supplying balanced nested brackets. Attackers can submit crafted Markdown with thousands of nested bracket pairs not forming a valid link, triggering repeated _contains_nested_link scans that exhaust CPU in parsing applications.
🔗 References (5)
- https://github.com/lepture/mistune/security/advisories/GHSA-47p6-w2rc-5qf7
- https://nvd.nist.gov/vuln/detail/CVE-2026-121438
- https://github.com/lepture/mistune/commit/fe02f40faf091f86da9ed62c865f31e11da111d7
- https://www.vulncheck.com/advisories/mistune-before-3.3.3-denial-of-service-via-balanced-bracket-link-parsing
- https://github.com/advisories/GHSA-296h-qmjr-9mv2