CVE-2026-74800: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
SiYuan before v3.7.4 fails to set Content-Disposition and X-Content-Type-Options headers when serving arbitrary file assets, allowing stored cross-site scripting attacks. Authenticated attackers can upload HTML files as assets and execute scripts with full kernel API access when the workspace owner opens the asset link.
AI Analysis
Technical Summary
CVE-2026-74800 describes a stored cross-site scripting vulnerability in SiYuan note-taking software prior to version 3.7.4. The software fails to set Content-Disposition and X-Content-Type-Options HTTP headers when serving arbitrary file assets, allowing authenticated attackers to upload HTML files containing malicious scripts. When the workspace owner opens the asset link, these scripts execute with full kernel API access, posing a severe security risk. The vulnerability has a CVSS 4.0 score of 9.4, indicating critical impact. No official remediation level or patch information is provided in the available data.
Potential Impact
An authenticated attacker can upload malicious HTML files as assets, which execute scripts with full kernel API access when the workspace owner opens the asset link. This can lead to full compromise of the affected system's kernel-level APIs, representing a critical security impact.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict authenticated user permissions to prevent uploading arbitrary file assets and avoid opening untrusted asset links.
CVE-2026-74800: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
Description
SiYuan before v3.7.4 fails to set Content-Disposition and X-Content-Type-Options headers when serving arbitrary file assets, allowing stored cross-site scripting attacks. Authenticated attackers can upload HTML files as assets and execute scripts with full kernel API access when the workspace owner opens the asset link.
CVSS v4.0
Score 9.4critical
Affected software
pkg:github/siyuan-note/siyuanRun 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-2026-74800 describes a stored cross-site scripting vulnerability in SiYuan note-taking software prior to version 3.7.4. The software fails to set Content-Disposition and X-Content-Type-Options HTTP headers when serving arbitrary file assets, allowing authenticated attackers to upload HTML files containing malicious scripts. When the workspace owner opens the asset link, these scripts execute with full kernel API access, posing a severe security risk. The vulnerability has a CVSS 4.0 score of 9.4, indicating critical impact. No official remediation level or patch information is provided in the available data.
Potential Impact
An authenticated attacker can upload malicious HTML files as assets, which execute scripts with full kernel API access when the workspace owner opens the asset link. This can lead to full compromise of the affected system's kernel-level APIs, representing a critical security impact.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict authenticated user permissions to prevent uploading arbitrary file assets and avoid opening untrusted asset links.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-08-16T12:59:42.223Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a82f001bf8831d539c482c9
Added to database: 08/17/2026, 11:26:57 UTC
Last enriched: 08/17/2026, 11:56:38 UTC
Last updated: 08/18/2026, 00:25:02 UTC
Views: 6
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