PT-2026-39307 · Pypi · Mistune

Sergeykochanov · Published 2026-05-08 · Updated 2026-05-26 · CVE-2026-44896

Positive Technologies (AI Summary)

CVSS v3.1

6.1

Medium

Base vector

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Name of the Vulnerable Software and Affected Versions Mistune (affected versions not specified)

Description The render figure() function in src/mistune/directives/image.py concatenates figclass and figwidth options directly into HTML attributes without escaping. This allows attribute injection and Cross-Site Scripting (XSS), a technique where malicious scripts are injected into trusted websites, even when HTMLRenderer(escape=True) is enabled, as these specific values bypass the inline renderer.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

XSS

Weakness Enumeration

CWE-79

Related Identifiers

CVE-2026-44896

GHSA-58CW-G322-P94V

PYSEC-2026-168

Affected Products

Mistune

References · 6

• https://github.com/lepture/mistune/security/advisories/GHSA-58cw-g322-p94v · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-58cw-g322-p94v · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-44896 · Security Note
• https://osv.dev/vulnerability/PYSEC-2026-168 · Vendor Advisory
• https://github.com/lepture/mistune · Note
• https://twitter.com/dailycve/status/2052955888705569060 · Twitter Post