CVE-2026-16089: Keycloak-services: keycloak-services: authorization codes can be retargeted to another client session

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-17 · updated 2026-09-16
Weakness: CWE-472

Description

A flaw was found in the keycloak-services component of Red Hat Build of Keycloak. The issue occurs because OAuth 2.0 authorization codes are not properly bound to the client that originally requested them. An attacker who can intercept an authorization code can modify it to be redeemed by their own client, potentially allowing them to obtain access tokens for a victim's identity.

Affected products

Red Hat build of Keycloak 26.4: all versions

References

https://access.redhat.com/errata/RHSA-2026:68277
https://access.redhat.com/errata/RHSA-2026:68278
https://access.redhat.com/security/cve/CVE-2026-16089
https://bugzilla.redhat.com/show_bug.cgi?id=2501724

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