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 + "\n")' | ./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 Upstream patch: https://github.com/github/cmark-gfm/commit/9d57d8a23142b316282bdfc954cb0ecda40a8655
Created ghc-cmark-gfm tracking bugs for this issue: Affects: fedora-all [bug 2128045] Created ghostwriter tracking bugs for this issue: Affects: fedora-all [bug 2128046] Created python-cmarkgfm tracking bugs for this issue: Affects: epel-8 [bug 2128048] Affects: fedora-all [bug 2128047]
For ghc-cmark-gfm I opened https://github.com/kivikakk/cmark-gfm-hs/issues/24