Description
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
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| github | cmark-gfm | < 0.29.0.gfm.7 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | cmark-gfm | 0.29.0.gfm.13-1 | — |
| Debian 14 | python-cmarkgfm | 2024.11.20-1 | — |
| Debian 14 | r-cran-commonmark | 1.9.0-1 | — |
| Debian 14 | ruby-commonmarker | 0.23.10-1 | — |
| Debian 13 | cmark-gfm | 0.29.0.gfm.13-1 | — |
| Debian 13 | python-cmarkgfm | 2024.11.20-1 | — |
| Debian 13 | r-cran-commonmark | 1.9.0-1 | — |
| Debian 13 | ruby-commonmarker | 0.23.10-1 | — |
| Debian 12 | cmark-gfm +3 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | cmark | No fix yet | — |
| Ubuntu 26.04 LTS | cmark | No fix yet | — |
| Ubuntu 25.10 | cmark | No fix yet | — |
| Ubuntu 24.04 LTS | cmark | No fix yet | — |
| Ubuntu 22.04 LTS | cmark | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | cmark | No fix yet | — |
| Ubuntu 18.04 LTS | cmark | No fix yet | — |
| Ubuntu Pro 24.04 LTS | cmark-gfm | 0.29.0.gfm.6-6ubuntu0.24.04.1~esm1 | USN-7319-1 |
| Ubuntu Pro 22.04 LTS | cmark-gfm | 0.29.0.gfm.3-3ubuntu0.1~esm1 | USN-7319-1 |
| Ubuntu Pro 20.04 LTS | cmark-gfm | 0.29.0.gfm.0-4ubuntu0.1~esm1 | USN-7319-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP4 | cmark | 0.30.2-150400.3.3.1 | SUSE-SU-2023:1834-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | cmark | 0.30.3-1.1 | openSUSE-SU-2024:12802-1 |
| openSUSE Leap 15.4 | cmark | 0.30.2-150400.3.3.1 | SUSE-SU-2023:1834-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | cmark | 0.30.3-r0 | — |
| Alpine v3.23 | cmark | 0.30.3-r0 | — |
| Alpine v3.22 | cmark | 0.30.3-r0 | — |
| Alpine v3.21 | cmark | 0.30.3-r0 | — |
| Alpine v3.20 | cmark | 0.30.3-r0 | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | cmark | 0.30.3-r0 | — |
| Alpine v3.18 | cmark | 0.30.3-r0 | — |
| Alpine v3.17 | cmark | 0.30.3-r0 | — |
Advisories 3
- USN-7319-1 cmark-gfm vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- SUSE-SU-2023:1834-1 Security update for cmark SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:12802-1 cmark-0.30.3-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026