SiYuan up to 3.6.0 WebSocket Endpoint /ws improper authentication

Summaryinfo

A vulnerability, which was classified as critical, has been found in SiYuan up to 3.6.0. This affects an unknown part of the file /ws of the component WebSocket Endpoint. This manipulation causes improper authentication. This vulnerability appears as CVE-2026-32815. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in SiYuan up to 3.6.0. Affected by this vulnerability is an unknown functionality of the file /ws of the component WebSocket Endpoint. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality. The summary by CVE is:

SiYuan is a personal knowledge management system. In versions 3.6.0 and below, the WebSocket endpoint (/ws) allows unauthenticated connections when specific URL parameters are provided (?app=siyuan&id=auth&type=auth). This bypass, intended for the login page to keep the kernel alive, allows any external client — including malicious websites via cross-origin WebSocket — to connect and receive all server push events in real-time. These events leak sensitive document metadata including document titles, notebook names, file paths, and all CRUD operations performed by authenticated users. Combined with the absence of Origin header validation, a malicious website can silently connect to a victim's local SiYuan instance and monitor their note-taking activity. This issue has been fixed in version 3.6.1.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-32815 since 03/16/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

Upgrading to version 3.6.1 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 1e370e37359778c0932673e825182ff555b504a3 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• SiYuan

Version

• 3.0
• 3.1
• 3.2
• 3.3
• 3.4
• 3.5
• 3.6.0

License

• open-source

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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