PyPI/mistune CVE-2026-59929: medium 6.1, EPSS 0.34%

Mistune renderers/html.safe_url: HARMFUL_PROTOCOLS list misses legacy and chained schemes that historically chain to `javascript:` execution

Action: Upgrade mistune to 3.3.0 or later.

pip install mistune==3.3.0

Affected

Fixed versions

Sources

• osv: GHSA-qfrw-5rxm-mhh2
• https://github.com/lepture/mistune/security/advisories/GHSA-qfrw-5rxm-mhh2
• https://nvd.nist.gov/vuln/detail/CVE-2026-59929
• https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc
• https://github.com/lepture/mistune
• https://github.com/lepture/mistune/releases/tag/v3.3.0
• https://github.com/pypa/advisory-database/tree/main/vulns/mistune/PYSEC-2026-2217.yaml

CVE-2026-59929 · published 2026-07-20T21:35:30Z · modified 2026-07-20T21:46:41.246867209Z · JSON