CVE-2026-82651

MEDIUM 4.9

SiYuan before v3.8.1 Missing Authorization via /history and /repo/diff

CVSS Score

4.9

EPSS Score

0.0%

EPSS Percentile

0th

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/.

CWE	CWE-200
Vendor	siyuan-note
Product	siyuan
Published	Aug 30, 2026

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CVSS v3 Breakdown

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Affected Versions

siyuan-note / siyuan

0 < 3.8.1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

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

Credits

🔍 alham-rizvi