CVE-2026-23645CWE-79

SiYuan Vulnerable to Stored Cross-Site Scripting (XSS) via Unrestricted SVG File Upload

Medium · published January 16, 2026

CVSS v4.0
5.3
EPSS
0%
Percentile
19.4
In the wild
Unconfirmed
What it is

SiYuan is self-hosted, open source personal knowledge management software. Prior to 3.5.4-dev2, a Stored Cross-Site Scripting (XSS) vulnerability exists in SiYuan Note. The application does not sanitize uploaded SVG files. If a user uploads and views a malicious SVG file (e.g., imported from an untrusted source), arbitrary JavaScript code is executed in the context of their authenticated session. This vulnerability is fixed in 3.5.4-dev2.

The record
Technical detail
CVSS v4.0
5.3 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
EPSS
0.00280 · 19.4th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-01-16T19:20Z
EPSS history
Timeline
  • 16 JAN 19:20Z
    SiYuan Vulnerable to Stored Cross-Site Scripting (XSS) via Unrestricted SVG File Upload
    cvelistv5