CVE-2026-105829GHSA-97jj-33gv-5xf9
League CommonMark 1.3.0 before 2.10.2 Stored XSS via DisallowedRawHtml Bypass
thephpleague commonmarkPackagistLibraries & packages
CVSS
5.3MediumExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 10 Oct 2026. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)0.20%Chance of exploitation activity in the next 30 days, higher than 9% of CVEs. Scored 23 Oct 2026FIRST EPSS
What fixes it
- 2.10.2league/commonmark, PackagistOSV
composer require "league/commonmark:^2.10.2"
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Description
League CommonMark from 1.3.0 before 2.10.2 contains a cross-site scripting vulnerability that allows users posting Markdown to bypass the DisallowedRawHtml extension by ending raw HTML with a bare disallowed tag name. Attackers can place a lone <script or <iframe line followed by a block supplying attributes like src or onload, executing stored scripts in viewers' browsers under default GFM settings.
Text from CVE List
Affected versions 51
- league/commonmark, Packagistfrom 1.3.0, fixed in 2.10.2OSV
- league/commonmark, Packagist1.3.0OSV
- league/commonmark, Packagist1.3.1OSV
- league/commonmark, Packagist1.3.2OSV
- league/commonmark, Packagist1.3.3OSV
- league/commonmark, Packagist1.3.4OSV
- league/commonmark, Packagist1.4.0OSV
- league/commonmark, Packagist1.4.1OSV
- league/commonmark, Packagist1.4.2OSV
- league/commonmark, Packagist1.4.3OSV
- league/commonmark, Packagist1.5.0OSV
- league/commonmark, Packagist1.5.1OSV
- league/commonmark, Packagist1.5.2OSV
- league/commonmark, Packagist1.5.3OSV
- league/commonmark, Packagist1.5.4OSV
- league/commonmark, Packagist1.5.5OSV
- league/commonmark, Packagist1.5.6OSV
- league/commonmark, Packagist1.5.7OSV
- league/commonmark, Packagist1.5.8OSV
- league/commonmark, Packagist1.6.0OSV
- league/commonmark, Packagist1.6.1OSV
- league/commonmark, Packagist1.6.2OSV
- league/commonmark, Packagist1.6.3OSV
- league/commonmark, Packagist1.6.4OSV
- league/commonmark, Packagist1.6.5OSV
- league/commonmark, Packagist1.6.6OSV
- league/commonmark, Packagist1.6.7OSV
- league/commonmark, Packagist2.0.0OSV
- league/commonmark, Packagist2.0.0-beta1OSV
- league/commonmark, Packagist2.0.0-beta2OSV
- league/commonmark, Packagist2.0.0-beta3OSV
- league/commonmark, Packagist2.0.0-rc1OSV
- league/commonmark, Packagist2.0.0-rc2OSV
- league/commonmark, Packagist2.0.1OSV
- league/commonmark, Packagist2.0.2OSV
- league/commonmark, Packagist2.0.3OSV
- league/commonmark, Packagist2.0.4OSV
- league/commonmark, Packagist2.1.0OSV
- league/commonmark, Packagist2.1.1OSV
- league/commonmark, Packagist2.1.2OSV
- league/commonmark, Packagist2.1.3OSV
- league/commonmark, Packagist2.10.0OSV
- league/commonmark, Packagist2.10.1OSV
- league/commonmark, Packagist2.2.0OSV
- league/commonmark, Packagist2.2.1OSV
- league/commonmark, Packagist2.2.2OSV
- league/commonmark, Packagist2.2.3OSV
- league/commonmark, Packagist2.2.4OSV
- league/commonmark, Packagist2.2.5OSV
- league/commonmark, Packagist2.3.0OSV
- league/commonmark, Packagist2.3.1OSV