CVE-2026-86712 (GCVE-0-2026-86712)

Vulnerability from cvelistv5 – Published: 2026-09-08 11:23 – Updated: 2026-09-10 15:03
VLAI
Title
SiYuan before 3.8.2 Remote Code Execution via Clipboard
Summary
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.
Severity
8.6 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-10 14:27 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 8184 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
siyuan-note siyuan Affected: 0 , < 3.8.2 (semver)
    cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-28 00:00
Credits
Siyang Wu
Show details on NVD website
To clipboard 

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