CVE-2026-74800

critical

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.

References

https://www.vulncheck.com/advisories/siyuan-before-stored-xss-via-assets-endpoint

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mjf3-jwmf-r6wf

Details

Source: Mitre, NVD

Published: 2026-08-17

Updated: 2026-08-17

Risk Information

CVSS v2

Base Score: 9

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 9

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H

Severity: Critical

CVSS v4

Base Score: 9.4

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Severity: Critical