Vulnerability in Red Hat Build Of Keycloak

CVE-2026-3429

A flaw was identified in the Account REST API of Keycloak that allows a user authenticated at a lower security level to perform sensitive actions intended only for higher-assurance sessions. Specifically, an attacker who has already obtained a victim’s password can delete the victim’s registered MFA/OTP credential without first proving possession of that factor. The attacker can then register their own MFA device, effectively taking full control of the account. This weakness undermines the intended protection provided by multi-factor authentication.

EPSS: 0.003 (16.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-3429?
CVE-2026-3429 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Improper Access Control. CVSS score: 4.2/10. Published 2026-03-11.
How severe is CVE-2026-3429?
Medium severity. CVSS v3 base score is 4.2 out of 10.