CVE-2023-22486: GitHub Cmark-Gfm

High severity, CVSS 7.5. EPSS: 1.1% chance of exploitation in the next 30 days.

cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. Versions prior to 0.29.0.gfm.7 contain a polynomial time complexity issue in handle_close_bracket that may lead to unbounded resource exhaustion and subsequent denial of service. This vulnerability has been patched in 0.29.0.gfm.7.

Affected products

• GitHub Cmark-Gfm: before 0.29.0.gfm.7 (fixed in 0.29.0.gfm.7)

Published 2023-01-26. Last modified 2026-06-17.