CVE-2026-82651

SiYuan before v3.8.1 does not apply the IsForbiddenAbsPath guard (introduced in GHSA-c8r8-95hg-mp34) to the /history/*path and /repo/diff/*path endpoints in kernel/server/serve.go. These routes require admin authentication but construct file paths independently, so an authenticated administrator can retrieve historical snapshots of sensitive files that the guard is meant to block, including data/.siyuan/publishAccess.json (plaintext publish-mode passwords) and files under data/templates/.

CVSS v3 4.9 MEDIUM

4.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

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-3cm4-ccvw-6xr6
https://www.vulncheck.com/advisories/siyuan-before-3.8.1-missing-authorization-via-history-and-repo-diff

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-30 15:16

Updated : 2026-08-31 20:56

NVD link : CVE-2026-82651

Mitre link : CVE-2026-82651

CVE.ORG link : CVE-2026-82651

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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