What is CVE-2026-87813?

CVE-2026-87813 is a high-severity vulnerability in Siyuan-Note Siyuan, classified under Cross-site Scripting. CVSS score: 7.3/10. Published 2026-09-09.

How severe is CVE-2026-87813?

High severity. CVSS v3 base score is 7.3 out of 10.

XSS in Siyuan-Note Siyuan

CVE-2026-87813

SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the Search Assets result list where asset filenames are interpolated into HTML without escaping. Authenticated attackers can craft asset filenames containing malicious markup that executes JavaScript in the victim's browser when searching assets, enabling same-origin API requests and application state manipulation.

Vulnerability class: XSS (Cross-Site Scripting)

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N.

Affected products

Siyuan-note Siyuan

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

disclosure@vulncheck.com (vendor-advisory)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-87813?: CVE-2026-87813 is a high-severity vulnerability in Siyuan-Note Siyuan, classified under Cross-site Scripting. CVSS score: 7.3/10. Published 2026-09-09.
How severe is CVE-2026-87813?: High severity. CVSS v3 base score is 7.3 out of 10.