CVE-2026-39846: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
SiYuan is a personal knowledge management system. Prior to 3.6.4, a malicious note synced to another user can trigger remote code execution in the SiYuan Electron desktop client. The root cause is that table caption content is stored without safe escaping and later unescaped into rendered HTML, creating a stored XSS sink. Because the desktop renderer runs with nodeIntegration enabled and contextIsolation disabled, attacker-controlled JavaScript executes with access to Node.js APIs. In practice, an attacker can import a crafted note into a synced workspace, wait for the victim to sync, and achieve code execution when the victim opens the note. This vulnerability is fixed in 3.6.4.
AI Analysis
Technical Summary
SiYuan versions before 3.6.4 contain a stored XSS vulnerability in the handling of table caption content. The content is saved without safe escaping and later injected into the rendered HTML in the Electron desktop client. Because the client runs with nodeIntegration enabled and contextIsolation disabled, the injected JavaScript can execute with Node.js privileges, enabling remote code execution. Exploitation requires an attacker to import a crafted note into a synced workspace and wait for the victim to sync and open the note. This vulnerability has been addressed in SiYuan version 3.6.4.
Potential Impact
Successful exploitation allows remote code execution on the victim's machine running the SiYuan Electron desktop client. This can lead to full compromise of the user's environment due to the elevated privileges granted by the Electron configuration. The vulnerability affects confidentiality, integrity, and availability of the affected system. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Upgrade SiYuan to version 3.6.4 or later, where this vulnerability is fixed. No other mitigations are specified. Patch status is not explicitly stated but the vendor has fixed the issue in version 3.6.4, so updating to this version is the recommended remediation.
CVE-2026-39846: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
Description
SiYuan is a personal knowledge management system. Prior to 3.6.4, a malicious note synced to another user can trigger remote code execution in the SiYuan Electron desktop client. The root cause is that table caption content is stored without safe escaping and later unescaped into rendered HTML, creating a stored XSS sink. Because the desktop renderer runs with nodeIntegration enabled and contextIsolation disabled, attacker-controlled JavaScript executes with access to Node.js APIs. In practice, an attacker can import a crafted note into a synced workspace, wait for the victim to sync, and achieve code execution when the victim opens the note. This vulnerability is fixed in 3.6.4.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
SiYuan versions before 3.6.4 contain a stored XSS vulnerability in the handling of table caption content. The content is saved without safe escaping and later injected into the rendered HTML in the Electron desktop client. Because the client runs with nodeIntegration enabled and contextIsolation disabled, the injected JavaScript can execute with Node.js privileges, enabling remote code execution. Exploitation requires an attacker to import a crafted note into a synced workspace and wait for the victim to sync and open the note. This vulnerability has been addressed in SiYuan version 3.6.4.
Potential Impact
Successful exploitation allows remote code execution on the victim's machine running the SiYuan Electron desktop client. This can lead to full compromise of the user's environment due to the elevated privileges granted by the Electron configuration. The vulnerability affects confidentiality, integrity, and availability of the affected system. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Upgrade SiYuan to version 3.6.4 or later, where this vulnerability is fixed. No other mitigations are specified. Patch status is not explicitly stated but the vendor has fixed the issue in version 3.6.4, so updating to this version is the recommended remediation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-07T19:13:20.378Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d57b23aaed68159a6dfc1b
Added to database: 4/7/2026, 9:46:11 PM
Last enriched: 4/7/2026, 10:01:29 PM
Last updated: 4/7/2026, 11:23:56 PM
Views: 7
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