CVE-2026-1011CWE-116CWE-79

Stored Cross-Site Scripting in Altium Live Support Center Comment Endpoint

Medium · published January 15, 2026

CVSS v3.1
6.1
EPSS
0%
Percentile
19.9
In the wild
Unconfirmed
What it is

A stored cross-site scripting (XSS) vulnerability exists in the Altium Support Center AddComment endpoint due to missing server-side input sanitization. Although the client interface applies HTML escaping, the backend accepts and stores arbitrary HTML and JavaScript supplied via modified POST requests.

The injected content is rendered verbatim when support cases are viewed by other users, including support staff with elevated privileges, allowing execution of arbitrary JavaScript in the victim’s browser context.

The record
Technical detail
CVSS v3.1
6.1 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00285 · 19.9th percentile
Weaknesses
CWE-116 · Improper Encoding or Escaping of Output; CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-01-15T23:08Z
EPSS history
Timeline
  • 15 JAN 23:08Z
    Stored Cross-Site Scripting in Altium Live Support Center Comment Endpoint
    cvelistv5