CVE-2026-1181: Altium 365

Critical severity, CVSS 9.0. EPSS: 0.4% chance of exploitation in the next 30 days.

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 products

• Altium Altium 365: affected versions not specified

Published 2026-01-19. Last modified 2026-06-17.