CVE-2023-3597: Keycloak: secondary factor bypass in step-up authentication

Severity: medium (CVSS 5.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-04-25 · updated 2026-06-17
Weakness: CWE-287

Description

A flaw was found in Keycloak, where it does not correctly validate its client step-up authentication in org.keycloak.authentication. This flaw allows a remote user authenticated with a password to register a false second authentication factor along with an existing one and bypass authentication.

Affected products

Red Hat build of Keycloak 22: all versions — fixed in 22-13, 22-16, 22.0.10-1

How to fix

Upgrade to a fixed version: Red Hat build of Keycloak 22 22-13, 22-16, 22.0.10-1. Check the vendor advisory for mitigations.

References

https://access.redhat.com/errata/RHSA-2024:1866
https://access.redhat.com/errata/RHSA-2024:1867
https://access.redhat.com/errata/RHSA-2024:1868
https://access.redhat.com/security/cve/CVE-2023-3597
https://bugzilla.redhat.com/show_bug.cgi?id=2221760
https://access.redhat.com/errata/RHSA-2024:1867
https://access.redhat.com/errata/RHSA-2024:1868
https://access.redhat.com/security/cve/CVE-2023-3597
https://bugzilla.redhat.com/show_bug.cgi?id=2221760

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