CVE-2026-93923: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
SiYuan through 3.8.4 fails to escape heading style attributes when rendering outline and bookmark dock HTML, allowing stored cross-site scripting. Attackers can supply crafted notebooks or call administrative endpoints to inject malicious style values that execute in the Electron renderer with full system access.
AI Analysis
Technical Summary
CVE-2026-93923 describes a stored cross-site scripting vulnerability in SiYuan note-taking software through version 3.8.4. The vulnerability arises from failure to properly escape heading style attributes when rendering outline and bookmark dock HTML. Attackers can exploit this by supplying crafted notebooks or invoking administrative endpoints to inject malicious style values. These values execute within the Electron renderer context, granting full system access to the attacker. The vulnerability has a CVSS 4.0 base score of 8.6, indicating high severity.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary code with full system access within the Electron renderer environment. This can lead to complete compromise of the affected system running SiYuan note software versions up to 3.8.4.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid opening untrusted notebooks and restrict access to administrative endpoints to trusted users only.
CVE-2026-93923: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
Description
SiYuan through 3.8.4 fails to escape heading style attributes when rendering outline and bookmark dock HTML, allowing stored cross-site scripting. Attackers can supply crafted notebooks or call administrative endpoints to inject malicious style values that execute in the Electron renderer with full system access.
CVSS v4.0
Score 8.6high
Affected software
siyuan-note
siyuan
pkg:golang/github.com/siyuan-note/siyuan/kernelRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-93923 describes a stored cross-site scripting vulnerability in SiYuan note-taking software through version 3.8.4. The vulnerability arises from failure to properly escape heading style attributes when rendering outline and bookmark dock HTML. Attackers can exploit this by supplying crafted notebooks or invoking administrative endpoints to inject malicious style values. These values execute within the Electron renderer context, granting full system access to the attacker. The vulnerability has a CVSS 4.0 base score of 8.6, indicating high severity.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary code with full system access within the Electron renderer environment. This can lead to complete compromise of the affected system running SiYuan note software versions up to 3.8.4.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid opening untrusted notebooks and restrict access to administrative endpoints to trusted users only.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-18T21:57:00.454Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6aadc9f655bf5e2cf5afb7a0
Added to database: 09/18/2026, 23:32:06 UTC
Last enriched: 09/18/2026, 23:46:30 UTC
Last updated: 09/19/2026, 01:17:24 UTC
Views: 6
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