SiYuan up to 3.6.4 Notification Message pushMsg msg os command injection

Summaryinfo

A vulnerability was found in SiYuan up to 3.6.4 and classified as critical. This vulnerability affects unknown code of the file /api/notification/pushMsg of the component Notification Message Handler. The manipulation of the argument msg results in os command injection. This vulnerability was named CVE-2026-41421. The attack needs to be approached locally. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in SiYuan up to 3.6.4. It has been classified as critical. Affected is an unknown code of the file /api/notification/pushMsg of the component Notification Message Handler. The manipulation of the argument msg with an unknown input leads to a os command injection vulnerability. CWE is classifying the issue as CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

SiYuan is an open-source personal knowledge management system. Prior to 3.6.5, SiYuan desktop renders notification messages as raw HTML inside an Electron renderer. The notification route POST /api/notification/pushMsg accepts a user-controlled msg value, forwards it through the backend broadcast layer, and the frontend inserts it into the DOM with insertAdjacentHTML(...) at message.ts. On desktop builds, this is not limited to ordinary XSS. Electron windows are created with nodeIntegration: true, contextIsolation: false, and webSecurity: false at main.js. As a result, JavaScript executed from the notification sink can directly access Node APIs and escalate to desktop code execution. This vulnerability is fixed in 3.6.5.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-41421 since 04/20/2026. The exploitability is told to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1202 by the MITRE ATT&CK project.

Upgrading to version 3.6.5 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25614). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

• SiYuan

Version

• 3.6.0
• 3.6.1
• 3.6.2
• 3.6.3
• 3.6.4

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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