CVE-2026-115355

CVSS 8.7 (high) · published 2026-10-22

Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.

Weakness: CWE-22

Source: NVD CVE-2026-115355

References

• https://github.com/lepture/mistune/security/advisories/GHSA-h7ww-273w-6cm8
• https://www.vulncheck.com/advisories/mistune-before-3.3.0-path-traversal-and-xss-via-include-directive

Check your software

Connect an AI agent to the FixLane MCP server or ask the Telegram bot to check what you have installed against incidents with a verified fixed version.