CVE-2026-59929

NameCVE-2026-59929
DescriptionMistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url filter in src/mistune/renderers/html.py blocks only javascript:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
mistune (PTS)bullseye0.8.4-4vulnerable
bookworm2.0.4-1vulnerable
trixie3.1.3-1vulnerable
forky, sid3.1.4-1vulnerable

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
mistunesource(unstable)(unfixed)

Notes

https://github.com/lepture/mistune/security/advisories/GHSA-qfrw-5rxm-mhh2
Fixed by: https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc (v3.3.0)

Search for package or bug name: Reporting problems