CVE-2026-44896 (GCVE-0-2026-44896)

Vulnerability from cvelistv5 – Published: 2026-05-26 20:33 – Updated: 2026-06-08 23:34
VLAI
Title
Mistune: XSS via unescaped figclass/figwidth in Figure directive
Summary
Mistune is a Python Markdown parser with renderers and plugins. In 3.2.0 and earlier, in src/mistune/directives/image.py, the render_figure() function concatenates figclass and figwidth options directly into HTML attributes without escaping. This allows attribute injection and XSS even when HTMLRenderer(escape=True) is used, because these values bypass the inline renderer. Version 3.2.1 contains a patch.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-27 13:06 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7625 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
lepture mistune Affected: < 3.2.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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