CVE-2026-86430

league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform super-linear work on crafted input. Attackers can submit specially crafted Markdown with long...

CVE-2026-86430

league/commonmark (a PHP Markdown parsing library) versions before 2.9.1 are affected by multiple denial-of-service vulnerabilities in three components: fenced code block detection , reference link label lookup , and emphasis delimiter processing . The root cause is super-linear work performed on...

GHSA-J8PM-GJ4C-RQ4X league/commonmark: Denial of service via crafted code fences, reference links, and emphasis delimiters

Impact Affected versions of league/commonmark perform super-linear work on three independent parsing paths, all of which are reachable on a stock new CommonMarkConverter with default configuration and no extensions registered. Each trigger fits on a single line of input, so no complex Markdown...