CVE-2026-40922: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
SiYuan is an open-source personal knowledge management system. In versions 3.6.1 through 3.6.3, a prior fix for XSS in bazaar README rendering (incomplete fix for CVE-2026-33066) enabled the Lute HTML sanitizer, but the sanitizer does not block iframe tags, and its URL-prefix blocklist does not effectively filter srcdoc attributes which contain raw HTML rather than URLs. A malicious bazaar package author can include an iframe with a srcdoc attribute containing embedded scripts in their README. When other users view the package in SiYuan's marketplace UI, the payload executes in the Electron context with full application privileges, enabling arbitrary code execution on the user's machine. This issue has been fixed in version 3.6.4.
AI Analysis
Technical Summary
SiYuan, an open-source personal knowledge management system, had an incomplete fix for an XSS vulnerability in its bazaar README rendering component. The Lute HTML sanitizer enabled in versions 3.6.1 through 3.6.3 does not block iframe tags and its URL-prefix blocklist does not effectively filter srcdoc attributes, which can contain raw HTML including scripts. A malicious bazaar package author can exploit this by embedding an iframe with a crafted srcdoc attribute in their README. When other users view this README in the marketplace UI, the embedded scripts execute within the Electron application context, granting full application privileges and enabling arbitrary code execution. This vulnerability is addressed in version 3.6.4.
Potential Impact
Successful exploitation allows a malicious bazaar package author to execute arbitrary code on the victim's machine with full application privileges via the Electron context. This can lead to compromise of the user's system and data. The vulnerability affects SiYuan versions prior to 3.6.4. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
Upgrade SiYuan to version 3.6.4 or later, where this vulnerability has been fixed. Since the vendor advisory indicates the issue is resolved in 3.6.4, applying this official fix is the recommended remediation. No additional mitigations are specified.
CVE-2026-40922: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
Description
SiYuan is an open-source personal knowledge management system. In versions 3.6.1 through 3.6.3, a prior fix for XSS in bazaar README rendering (incomplete fix for CVE-2026-33066) enabled the Lute HTML sanitizer, but the sanitizer does not block iframe tags, and its URL-prefix blocklist does not effectively filter srcdoc attributes which contain raw HTML rather than URLs. A malicious bazaar package author can include an iframe with a srcdoc attribute containing embedded scripts in their README. When other users view the package in SiYuan's marketplace UI, the payload executes in the Electron context with full application privileges, enabling arbitrary code execution on the user's machine. This issue has been fixed in version 3.6.4.
CVSS v4.0
Score 5.3medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
SiYuan, an open-source personal knowledge management system, had an incomplete fix for an XSS vulnerability in its bazaar README rendering component. The Lute HTML sanitizer enabled in versions 3.6.1 through 3.6.3 does not block iframe tags and its URL-prefix blocklist does not effectively filter srcdoc attributes, which can contain raw HTML including scripts. A malicious bazaar package author can exploit this by embedding an iframe with a crafted srcdoc attribute in their README. When other users view this README in the marketplace UI, the embedded scripts execute within the Electron application context, granting full application privileges and enabling arbitrary code execution. This vulnerability is addressed in version 3.6.4.
Potential Impact
Successful exploitation allows a malicious bazaar package author to execute arbitrary code on the victim's machine with full application privileges via the Electron context. This can lead to compromise of the user's system and data. The vulnerability affects SiYuan versions prior to 3.6.4. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
Upgrade SiYuan to version 3.6.4 or later, where this vulnerability has been fixed. Since the vendor advisory indicates the issue is resolved in 3.6.4, applying this official fix is the recommended remediation. No additional mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-15T20:40:15.517Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e1716682d89c981fde6ff9
Added to database: 4/16/2026, 11:31:50 PM
Last enriched: 4/24/2026, 4:05:09 PM
Last updated: 5/31/2026, 4:14:45 PM
Views: 80
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