CVE-2026-33067: b3log siyuan Cross-site Scripting

Vulnerability summary

CVE-2026-33067 is a critical (CVSS 9.0) Cross-site Scripting vulnerability in b3log siyuan. EPSS estimates a 0.68% chance of exploitation in the next 30 days, higher than 51.4% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 20-03-2026
   PublishedVulnerability first disclosed.
2. 20-03-2026
   Last modifiedVulnerability information updated.

Description

SiYuan is a personal knowledge management system. Versions 3.6.0 and below render package metadata fields (displayName, description) using template literals without HTML escaping. A malicious package author can inject arbitrary HTML/JavaScript into these fields, which executes automatically when any user browses the Bazaar page. Because SiYuan's Electron configuration enables nodeIntegration: true with contextIsolation: false, this XSS escalates directly to full Remote Code Execution on the victim's operating system — with zero user interaction beyond opening the marketplace tab. This issue has been fixed in version 3.6.1.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.