CVE-2026-59922 (GCVE-0-2026-59922)
Vulnerability from cvelistv5
Published
2026-07-08 16:12
Modified
2026-07-09 14:40
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
  • CWE-1333 - Inefficient Regular Expression Complexity
Summary
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a run of closed tilde, equals-sign, or caret marker pairs around a character causes quadratic work in src/mistune/plugins/formatting.py when the strikethrough, mark, or insert plugin scans for matching markers from each possible start position, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
References
Impacted products
Vendor Product Version
lepture mistune Version: < 3.3.0
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