What is CVE-2026-56451?

CVE-2026-56451 is a critical-severity vulnerability in Siemens Opcenter X, classified under Improper Verification of Cryptographic Signature. CVSS score: 10.0/10. Published 2026-07-14.

How severe is CVE-2026-56451?

Critical severity. CVSS v3 base score is 10.0 out of 10.

Vulnerability in Siemens Opcenter X

CVE-2026-56451

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.

EPSS: 0.005 (40.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

Affected products

Siemens Opcenter X — versions 0

Weakness classification (CWE)

CWE-347 — Improper Verification of Cryptographic Signature

References

productcert@siemens.com

Frequently asked questions

What is CVE-2026-56451?: CVE-2026-56451 is a critical-severity vulnerability in Siemens Opcenter X, classified under Improper Verification of Cryptographic Signature. CVSS score: 10.0/10. Published 2026-07-14.
How severe is CVE-2026-56451?: Critical severity. CVSS v3 base score is 10.0 out of 10.