CVE-2026-86439

knowns versions before 0.30.0 fail to validate filesystem paths in MCP tool arguments, allowing attackers to read, create, overwrite and delete files outside the project directory. Attackers can supply path arguments containing directory traversal sequences to access arbitrary Markdown files accessible to the server process.

  • Published Sep 7, 2026
  • CVSS 8.7 high
  • 1.1% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-86439 at the National Vulnerability Database