CVE-2026-39846: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
CVE-2026-39846 is a critical stored cross-site scripting (XSS) vulnerability in SiYuan personal knowledge management system versions prior to 3. 6. 4. The flaw arises from unsafe handling of table caption content, which is stored without proper escaping and later rendered as unescaped HTML. Because the SiYuan Electron desktop client runs with nodeIntegration enabled and contextIsolation disabled, this allows attacker-controlled JavaScript to execute with full access to Node. js APIs, effectively enabling remote code execution. An attacker can exploit this by syncing a crafted malicious note to a victim's workspace, triggering code execution when the victim opens the note. This vulnerability is fixed in version 3. 6. 4.
AI Analysis
Technical Summary
SiYuan versions before 3.6.4 contain a stored XSS vulnerability due to improper neutralization of input in table caption content. The malicious content is stored without safe escaping and later injected into the HTML renderer unescaped. The Electron desktop client configuration (nodeIntegration enabled, contextIsolation disabled) allows the injected JavaScript to execute with Node.js API access, resulting in remote code execution. Exploitation requires an attacker to sync a crafted note to a victim's workspace and wait for the victim to open it. This vulnerability is addressed in SiYuan version 3.6.4.
Potential Impact
Successful exploitation leads to remote code execution on the victim's machine running the SiYuan Electron desktop client. This can compromise confidentiality, integrity, and availability of the affected system. The vulnerability is critical with a CVSS score of 9.1, reflecting network attack vector, low attack complexity, required privileges, user interaction, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Upgrade SiYuan to version 3.6.4 or later, where this vulnerability is fixed. No other mitigation or workaround is documented. Users running affected versions should apply the official update promptly to eliminate the risk of remote code execution via malicious synced notes.
CVE-2026-39846: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
Description
CVE-2026-39846 is a critical stored cross-site scripting (XSS) vulnerability in SiYuan personal knowledge management system versions prior to 3. 6. 4. The flaw arises from unsafe handling of table caption content, which is stored without proper escaping and later rendered as unescaped HTML. Because the SiYuan Electron desktop client runs with nodeIntegration enabled and contextIsolation disabled, this allows attacker-controlled JavaScript to execute with full access to Node. js APIs, effectively enabling remote code execution. An attacker can exploit this by syncing a crafted malicious note to a victim's workspace, triggering code execution when the victim opens the note. This vulnerability is fixed in version 3. 6. 4.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
SiYuan versions before 3.6.4 contain a stored XSS vulnerability due to improper neutralization of input in table caption content. The malicious content is stored without safe escaping and later injected into the HTML renderer unescaped. The Electron desktop client configuration (nodeIntegration enabled, contextIsolation disabled) allows the injected JavaScript to execute with Node.js API access, resulting in remote code execution. Exploitation requires an attacker to sync a crafted note to a victim's workspace and wait for the victim to open it. This vulnerability is addressed in SiYuan version 3.6.4.
Potential Impact
Successful exploitation leads to remote code execution on the victim's machine running the SiYuan Electron desktop client. This can compromise confidentiality, integrity, and availability of the affected system. The vulnerability is critical with a CVSS score of 9.1, reflecting network attack vector, low attack complexity, required privileges, user interaction, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Upgrade SiYuan to version 3.6.4 or later, where this vulnerability is fixed. No other mitigation or workaround is documented. Users running affected versions should apply the official update promptly to eliminate the risk of remote code execution via malicious synced notes.
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: 4/15/2026, 3:54:52 PM
Last updated: 5/22/2026, 4:20:13 AM
Views: 91
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