CVE-2022-39209 Information

Description

cmark-gfm is GitHub’s fork of cmark a CommonMark parsing and rendering library and program in C. In versions prior to 0.29.0.gfm.6 a polynomial time complexity issue in cmark-gfm’s autolink extension may lead to unbounded resource exhaustion and subsequent denial of service. Users may verify the patch by running python3 -c 'print(\![l\ 100000 + \ \)' | ./cmark-gfm -e autolink which will resource exhaust on unpatched cmark-gfm but render correctly on patched cmark-gfm. This vulnerability has been patched in 0.29.0.gfm.6. Users are advised to upgrade. Users unable to upgrade should disable the use of the autolink extension.

Reference

https://github.com/github/cmark-gfm/security/advisories/GHSA-cgh3-p57x-9q7q https://en.wikipedia.org/wiki/Time_complexity https://github.com/github/cmark-gfm/commit/9d57d8a23142b316282bdfc954cb0ecda40a8655