CVE-2022-39209
mediumpriority · track · 27EPSS 0.022 · 82 %ileDEEUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (8)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2022-1935Microsoft GitHub Enterprise: Mehrere SchwachstellenDeutsch2022-11-01csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Microsoft GitHub Enterprise ausnutzen, um Informationen offenzulegen oder einen Denial of Service Zustand herbeizuführen.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (20)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2022-39209/cnnvd
- https://en.wikipedia.org/wiki/Time_complexitycnnvd
- https://github.com/github/cmark-gfm/commit/9d57d8a23142b316282bdfc954cb0ecda40a8655cnnvd
- https://github.com/github/cmark-gfm/security/advisories/GHSA-cgh3-p57x-9q7qcnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JIUCZN3PEKUCT2JQYQTYOVIJG2KSD6G7/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JMGP65NANDVKPDMXMKYO2ZV2H2HZJY4P/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UEAAAI4OULDYQ2TA3HOXH54PC3DCBFZS/cnnvd
- https://vigilance.fr/vulnerability/cmark-gfm-overload-via-Autolink-Extension-39840cnnvd
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