Vulnerability · Published Sep 9, 2026 · Assigned by VulnCheck

CVE-2026-87813SiYuan before v3.8.2 Stored XSS via unescaped asset filenames

High 7.3

In plain English

A high-severity cross-site scripting in siyuan from siyuan-note. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 31% of all known vulnerabilities).

Severity (CVSS 3.1)7.3High

Exploit odds (30 days)0.4%top 69.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
siyuan-note	siyuan	0 – before 3.8.2

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

References

GitHub Security Advisory (GHSA-qcw6-qm34-28h8) vendor-advisory
VulnCheck Advisory: SiYuan before v3.8.2 Stored XSS via unescaped asset filenames third-party-advisory