CVE-2026-86712: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
Description
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.
CVSS v4.0
Score 8.6high
Affected software
siyuan-note
siyuan
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
SiYuan versions prior to 3.8.2 improperly neutralize input during web page generation by trusting the attacker-writable text/siyuan clipboard MIME type without sanitization in the paste handler. This leads to code execution in the Node-enabled desktop renderer. An attacker can craft malicious web pages that write to the clipboard, and when a user pastes this clipboard content into SiYuan, injected scripts execute with full Node.js access through the Electron main process.
Potential Impact
Successful exploitation allows remote code execution with full Node.js privileges in the Electron main process of the SiYuan desktop application. This can lead to complete compromise of the user's environment where SiYuan is running. The vulnerability requires user interaction (pasting clipboard content) but does not require prior authentication or privileges.
Mitigation Recommendations
A fix is available in SiYuan version 3.8.2 and later. Users should upgrade to version 3.8.2 or newer to remediate this vulnerability. No additional mitigations are specified in the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-08T10:58:25.497Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a9ff395acd9273b49949e40
Added to database: 09/08/2026, 11:37:57 UTC
Last enriched: 09/16/2026, 01:47:55 UTC
Last updated: 10/22/2026, 13:15:24 UTC
Views: 84
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.