Executive brief
SiYuan is an open-source personal knowledge management system. A security vulnerability in its community marketplace (Bazaar) allows malicious plugins or themes to execute unauthorized code on a user's computer. If a user simply views the marketplace or their list of installed plugins, a specially crafted package name or version number can trigger the attack. Because the desktop application has high-level system permissions, this can lead to a full takeover of the user's computer and data.
Technical details
A stored Cross-Site Scripting (XSS) vulnerability exists in SiYuan's Bazaar marketplace due to improper neutralization of the 'name' and 'version' fields in package manifest files (plugin.json, theme.json, etc.). While the 'sanitizePackageDisplayStrings' function in the Go-based kernel escapes other fields, it omits 'Name' and 'Version'. These unsanitized strings are passed to the frontend and injected into the DOM using 'innerHTML'. In the desktop client, Electron is configured with 'nodeIntegration: true' and 'contextIsolation: false', allowing the XSS payload to access Node.js APIs like 'child_process'. An attacker can achieve arbitrary OS command execution by submitting a malicious package to the public marketplace or tricking a user into installing one. The vulnerability is triggered when a user opens the Marketplace UI, requiring no further interaction.
Affected products
- SiYuan-Note SiYuan < 3.7.0
Timeline
- 2026-05-10: advisory: GitHub Security Advisory published
- 2026-05-14: disclosed: NVD publication date