CVE-2026-100642

SiYuan versions from v2.1.0 before v3.8.4 contain a cross-site request forgery vulnerability in the CheckAuth lock-screen pass-through branch that grants administrator access to loopback requests without validating Origin headers. Attackers can craft malicious web pages that force victims to terminate the kernel process, read workspace configuration and proxy settings, and trigger administrative actions via zero-credential cross-origin requests from the victim's browser.

CVSS v3 7.6 HIGH

7.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9gpj-3rm3-x42m
https://www.vulncheck.com/advisories/siyuan-2.1.0-before-3.8.4-cross-site-request-forgery-via-checkauth
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9gpj-3rm3-x42m

Configurations

No configuration.

History

30 Sep 2026, 15:17

Type	Values Removed	Values Added
References	~~() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9gpj-3rm3-x42m -~~	() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9gpj-3rm3-x42m -

26 Sep 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 14:16

Updated : 2026-09-30 15:17

NVD link : CVE-2026-100642

Mitre link : CVE-2026-100642

CVE.ORG link : CVE-2026-100642

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

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