What is CVE-2026-1011?

CVE-2026-1011 is a medium-severity vulnerability in Altium Live, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-01-16.

How severe is CVE-2026-1011?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Altium Live

CVE-2026-1011

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.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (17.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Altium Live — versions 0
Altium Altium_live

Weakness classification (CWE)

References

4760f414-e1ae-4ff1-bdad-c7a9c3538b79 (Vendor Advisory)

Frequently asked questions

What is CVE-2026-1011?: CVE-2026-1011 is a medium-severity vulnerability in Altium Live, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-01-16.
How severe is CVE-2026-1011?: Medium severity. CVSS v3 base score is 6.1 out of 10.