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CVE

CVE-2026-66394

SiYuan before v3.7.3 Stored and Reflected XSS via SVG Sanitizer Bypass
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CVE

CVE-2026-66394

SiYuan before v3.7.3 Stored and Reflected XSS via SVG Sanitizer Bypass

SiYuan before v3.7.3 contains stored and reflected cross-site scripting vulnerabilities in SVG sanitization that allows authenticated attackers to execute scripts by bypassing the HTML parser-based cleaner. Attackers can hide script tags within desc, style, or noscript elements which the HTML parser treats as raw text but browsers interpret as executable SVG content when served as image/svg+xml, enabling script execution in the application origin.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.3
-
4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-

Related Resources

No items found.

References

https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/66xxx/CVE-2026-66394.json, https://github.com/siyuan-note/siyuan/security/advisories/GHSA-99rq-75j6-5j9f, https://nvd.nist.gov/vuln/detail/CVE-2026-66394, https://www.vulncheck.com/advisories/siyuan-before-stored-and-reflected-xss-via-svg-sanitizer-bypass

Severity

0

CVSS Score
0
10

Basic Information

Base CVSS
0
EPSS Probability
0.00266%
EPSS Percentile
0.1892%
Introduced Version
0
Fix Available
eef10568384e2e7cf547adb029ae46a72e43c287

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