CVE-2026-95503
Keycloak-services: keycloak-services: potential kdc spoofing bypass when kerberos password authentication is enabled
What happened?
A flaw was found in the Kerberos federation provider of Keycloak, an open-source identity and access management solution. When Kerberos password authentication is used without SPNEGO, the system fails to verify the identity of the Key Distribution Center (KDC) by requesting a server ticket. This allows an attacker on the same network to spoof the KDC and bypass the authentication process, potentially gaining unauthorized access to user accounts.
Affected software and versions
| Software | Version information | Fixed version |
|---|---|---|
| keycloak/rhbk-openshift-rhel9Red Hat | Default status: unaffected | See vendor advisory |
| keycloak-servicesRed Hat | Default status: unaffected | See vendor advisory |
| rhbk/keycloak-rhel9Red Hat | Default status: unaffected | See vendor advisory |
| keycloak-servicesRed Hat | Default status: affected | See vendor advisory |
Version information comes from the source record and can include unaffected products and exceptions. Distribution packages may contain backported fixes: an older upstream version alone does not prove a server is affected.
Is it being exploited?
This CVE was not listed in the CISA catalogue at our last retrieval. This does not establish that exploitation is absent.
How to respond
- Confirm the product, installed package version, and any configuration requirements in the vendor advisory.
- Follow the vendor’s remediation or workaround guidance in the references below. Structured fixed-version data is unavailable here; the publisher’s description may include a fix or workaround.
- Restart affected services if required, then verify the running version. Known exploitation may warrant investigation as well as patching.