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 v3 7.6 HIGH

7.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
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

Configurations

No configuration.

History

05 Oct 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2 -~~	() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2 -

26 Sep 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 14:16

Updated : 2026-10-05 16:17

NVD link : CVE-2026-100637

Mitre link : CVE-2026-100637

CVE.ORG link : CVE-2026-100637

JSON object : View

Products Affected

No product.

CWE

CWE-73

External Control of File Name or Path

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