CVE catalog
CVE-2026-86430
league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform s
- Severity
- High · CVSS 8.7
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.49% · Oct 25, 2026
league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform super-linear work on crafted input. Attackers can submit specially crafted Markdown with long backtick runs, nested brackets, or delimiter sequences to consume disproportionate CPU time and prevent legitimate requests from completing.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | php-league-commonmark | sid | 2.10.4-1 | fixed |
| Debian | php-league-commonmark | forky | 2.10.4-1 | fixed |
| Debian | php-league-commonmark | trixie | 2.7.0-1+deb13u1 | vulnerable |
| Debian | php-league-commonmark | bookworm | 2.3.9-1+deb12u1 | vulnerable |
| Cpe | commonmark | Not reported | 2.9.1 | fixed |
| Ubuntu | php-league-commonmark | pro | 2.3.9-1 | vulnerable |
| Ubuntu | php-league-commonmark | pro | 2.4.1-1 | vulnerable |
| Ubuntu | php-league-commonmark | pro | 2.4.2-1 | vulnerable |
| Ubuntu | php-league-commonmark | pro | 2.4.2-2 | vulnerable |
| Ubuntu | php-league-commonmark | pro | 2.4.2-2ubuntu0.1~esm1 | vulnerable |
| Ubuntu | php-league-commonmark | 26.04 | 2.7.0-1 | vulnerable |
| Ubuntu | php-league-commonmark | 26.04 | 2.7.1-2 | vulnerable |
| Ubuntu | php-league-commonmark | 26.04 | 2.8.0-1 | vulnerable |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | php-league-commonmark | source | sid | 2.10.0-1 | not yet assigned | Not reported | Not reported |
| Debian | php-league-commonmark | source | forky | 2.10.0-1 | not yet assigned | Not reported | Not reported |
| Debian | php-league-commonmark | source | trixie | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | php-league-commonmark | source | bookworm | (unfixed) | not yet assigned | Not reported | Not reported |
| Cpe | commonmark | cpe | Not reported | 2.9.1 | Not reported | NVD-CVE-2026-86430 | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [php-league-commonmark]Affected
Details (2)
2.3.9-1+deb12u1· all · bookwormAffected
nvd · php-league-commonmark · debian · bookworm; nvd · php-league-commonmark · debian · 12
2.3.9-1+deb12u1· all · bookwormAffected
nvd · php-league-commonmark · debian · bookworm; nvd · php-league-commonmark · debian · 12
[Debian 13 (Trixie)]
- [php-league-commonmark]Affected
Details (2)
2.7.0-1+deb13u1· all · trixieAffected
nvd · php-league-commonmark · debian · 13
2.7.0-1+deb13u1· all · trixieAffected
nvd · php-league-commonmark · debian · 13
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2026-86430]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-86430]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-86430]
- [https://security-tracker.debian.org/tracker/CVE-2026-86430]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database]