CVE-2026-1181: Altium 365 Over-Permissive CORS Configuration Allows Credentialed Cross-Origin Workspace Access

Published Jan 19, 2026

Updated

Altium 365 workspace endpoints were configured with an overly permissive Cross-Origin Resource Sharing (CORS) policy that allowed credentialed cross-origin requests from other Altium-controlled subdomains, including forum.live.altium.com. As a result, JavaScript executing on those origins could access authenticated workspace APIs in the context of a logged-in user. When chained with vulnerabilities in those external applications, this misconfiguration enables unauthorized access to workspace data, administrative actions, and bypass of IP allowlisting controls, including in GovCloud environments.

Affected Software

1 affected component

Altium Altium 365

Event History

Jan 19, 2026

CVE Published

via MITRE·12:00 PM

Data Sourced

via MITRE·12:00 PM

DescriptionSeverityWeakness

Data Sourced

via NVD·01:16 PM

DescriptionSeverityWeakness

Mar 25, 58030

Event

via FIRST·08:09 PM

Frequently Asked Questions

What is the severity of CVE-2026-1181?

The severity of CVE-2026-1181 is considered high due to its potential for cross-customer data exposure.

How do I fix CVE-2026-1181?

To fix CVE-2026-1181, ensure that all user input in forum post content is properly sanitized on the server side.

What type of vulnerability is CVE-2026-1181?

CVE-2026-1181 is a stored cross-site scripting (XSS) vulnerability.

Who is affected by CVE-2026-1181?

CVE-2026-1181 affects users of the Altium 365 Forum who are exposed to untrusted content.

Can CVE-2026-1181 be exploited by unauthenticated users?

No, CVE-2026-1181 requires an authenticated attacker to exploit the vulnerability.