CVE-2026-100637

SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.

  • Published Sep 26, 2026
  • CVSS 8.3 high
  • 0.5% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-100637 at the National Vulnerability Database