CVE-2026-86712

SiYuan before 3.8.2 trusts the attacker-writable text/siyuan clipboard MIME type and skips sanitization in the paste handler, allowing code execution in the Node-enabled desktop renderer. Attackers can craft malicious web pages that write to the clipboard, and when pasted into SiYuan, injected scripts execute with full Node.js access through the Electron main process.

  • Published Sep 8, 2026
  • CVSS 8.6 high
  • 0.7% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-86712 at the National Vulnerability Database