CVE-2026-1011

Severity CVSS v4.0:

Pending analysis

Type:

CWE-79 Cross-Site Scripting (XSS)

Publication date:

16/01/2026

Last modified:

16/01/2026

Description

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.<br /> <br /> 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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 6.10 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Changed
Confidentiality (C): Low
Integrity (I): Low
Availability (A): None

Base Score 3.x

6.10

Severity 3.x

MEDIUM

References to Advisories, Solutions, and Tools

https://www.altium.com/platform/security-compliance/security-advisories