CVE-2026-56451: Siemens Opcenter X

Critical severity, CVSS 10.0. EPSS: 0.5% chance of exploitation in the next 30 days.

A vulnerability has been identified in Opcenter X (All versions < V2604). Affected applications do not properly validate the algorithm specified in the JSON Web Token (JWT) header. This could allow an unauthenticated remote attacker to forge arbitrary JWT, bypass authentication mechanisms and impersonate any user including administrative accounts, potentially gaining full unauthorized access to the application.

Affected products

• Siemens Opcenter X: before V2604 (fixed in V2604)

Published 2026-07-14. Last modified 2026-07-15.