CVE-2026-74902

SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file upload validation flow that fails to escape filenames before inserting them into HTML via insertAdjacentHTML. Attackers can craft a malicious filename containing script payloads that execute with full OS command access when a user drags, drops, or pastes the file into the editor.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

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-jf56-jrhq-j2qp
https://www.vulncheck.com/advisories/siyuan-before-xss-to-rce-via-malicious-filename-upload

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-18 12:19

Updated : 2026-08-26 17:04

NVD link : CVE-2026-74902

Mitre link : CVE-2026-74902

CVE.ORG link : CVE-2026-74902

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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