CVE-2026-74867
Received Received - Intake

Cross-Site Request Forgery in SiYuan Before 3.7.4

Publication date: 2026-08-17

Last updated on: 2026-08-17

Assigner: VulnCheck

Description
SiYuan versions before 3.7.4 contain a cross-site request forgery vulnerability in the session-cookie authentication branch of CheckAuth() that lacks Origin/Referer validation and sets no explicit SameSite attribute on session cookies. Attackers can craft malicious web pages that perform unauthorized actions on behalf of authenticated users by submitting requests with valid session cookies, relying on browser default SameSite policies rather than server-enforced protections.

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Meta Information

Published
2026-08-17
Last Modified
2026-08-17
Generated
2026-08-17
AI Q&A
2026-08-17
EPSS Evaluated
N/A
NVD
CVE-2026-74867
EUVD
EUVD-2026-60086

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
siyuan siyuan to 3.7.4 (exc)

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-352 The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.

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Executive Summary

This is a Cross-Site Request Forgery (CSRF) vulnerability in SiYuan versions before 3.7.4. The CheckAuth() function's session-cookie authentication branch lacks Origin/Referer validation and does not set an explicit SameSite attribute on session cookies. Attackers can exploit this by tricking authenticated users into visiting malicious pages that perform unauthorized actions using their valid session cookies.

Detection Guidance

Detecting this CSRF vulnerability requires checking if SiYuan versions before 3.7.4 are running and if session cookies lack SameSite attributes or Origin/Referer validation. Inspect network traffic for requests to SiYuan endpoints without proper CSRF protections. Use browser developer tools to examine cookie attributes for session cookies.

Impact Analysis

If you use SiYuan versions before 3.7.4, attackers could perform unauthorized actions on your behalf, such as modifying notes or accessing sensitive data, if you visit a malicious website while logged into SiYuan. The impact depends on your actions and data within the application.

Compliance Impact

This CSRF vulnerability could potentially impact compliance with GDPR and HIPAA by exposing user sessions to unauthorized actions. GDPR requires protecting personal data integrity, while HIPAA mandates secure access controls. The lack of SameSite cookie enforcement and Origin/Referer validation may violate these standards by allowing unauthorized data modifications or access.

Mitigation Strategies

Upgrade SiYuan to version 3.7.4 or later to address the vulnerability. Ensure session cookies explicitly set SameSite=Strict or SameSite=Lax. Implement Origin and Referer header validation in the CheckAuth() function's session-cookie branch. Monitor for unauthorized actions in application logs.

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