CVE-2026-85580

SiYuan versions before v3.8.2 contain a path guard bypass vulnerability in the MCP file-access handler that uses case-sensitive matching on Linux filesystems. Attackers can read the protected publishAccess.json file by requesting case-variant paths like PublishAccess.json to disclose sensitive publish-access configuration and metadata.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mmgw-3mx9-cfwp
https://www.vulncheck.com/advisories/siyuan-before-3.8.2-path-guard-bypass-via-case-mismatch
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mmgw-3mx9-cfwp

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-04 12:17

Updated : 2026-09-08 20:05

NVD link : CVE-2026-85580

Mitre link : CVE-2026-85580

CVE.ORG link : CVE-2026-85580

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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