CVE-2026-86712: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
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.
AI Analysis
Technical Summary
CVE-2026-86712 describes an improper neutralization of input during web page generation in SiYuan versions prior to 3.8.2. The vulnerability occurs because the paste handler accepts clipboard content labeled with the text/siyuan MIME type without sanitization. Malicious web pages can write crafted content to the clipboard, which when pasted into SiYuan, triggers script execution with full Node.js access via the Electron main process, enabling code execution on the victim's machine.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary code with full Node.js privileges in the context 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 privileges or authentication.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Users should upgrade to SiYuan version 3.8.2 or later once available. Until then, avoid pasting untrusted clipboard content into the application to reduce risk.
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
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-86712 describes an improper neutralization of input during web page generation in SiYuan versions prior to 3.8.2. The vulnerability occurs because the paste handler accepts clipboard content labeled with the text/siyuan MIME type without sanitization. Malicious web pages can write crafted content to the clipboard, which when pasted into SiYuan, triggers script execution with full Node.js access via the Electron main process, enabling code execution on the victim's machine.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary code with full Node.js privileges in the context 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 privileges or authentication.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Users should upgrade to SiYuan version 3.8.2 or later once available. Until then, avoid pasting untrusted clipboard content into the application to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-08T10:58:25.497Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a9ff395acd9273b49949e40
Added to database: 09/08/2026, 11:37:57 UTC
Last enriched: 09/08/2026, 11:52:18 UTC
Last updated: 09/08/2026, 18:27:40 UTC
Views: 10
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