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.

CVSS 4.0

8.3CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L

CVSS 3.1

7.6CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L

EPSS

0.6% chance of exploitation in the next 30 days; higher than 45% of CVEs (scores of 2026-10-25)

CWE

CWE-73

Published

2026-09-26

Modified

2026-10-05

Record from

the NVD, synced 2026-10-19

References

• https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2
• https://www.vulncheck.com/advisories/siyuan-before-3.8.4-path-traversal-via-checkoutrepo-sessionid
• https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2

Check your stackJSON