CVE-2026-74800

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 v3 9.0 CRITICAL

9.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mjf3-jwmf-r6wf
https://www.vulncheck.com/advisories/siyuan-before-stored-xss-via-assets-endpoint

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-17 11:16

Updated : 2026-08-26 17:04

NVD link : CVE-2026-74800

Mitre link : CVE-2026-74800

CVE.ORG link : CVE-2026-74800

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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