CVE-2026-76187 Apache Airflow Keycloak provider: Any realm client's credentials mint an Airflow session JWT
Attackers with credentials for any Keycloak realm client can authenticate to Airflow, bypassing intended client restrictions and gaining unauthorized access.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-76187?
CVE-2026-76187 is a critical authentication bypass vulnerability in Apache Airflow Keycloak provider, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Apache Airflow Keycloak provider: the unauthenticated token endpoint accepts a client-credentials grant for any confidential client registered in the Keycloak realm, not only the client configured for Airflow. No allowlist restricts which client ids may authenticate, so the credentials of an unrelated application that happens to share the realm are valid Airflow login credentials, and Airflow mints a signed session token for that application's service account. The endpoint also answers unauthenticated credential guesses against Keycloak under Airflow's identity.
Affects deployments using the Keycloak auth manager whose realm is shared with other confidential clients. The attacker needs valid credentials for any one of those clients, not for Airflow. Resource authorization is still evaluated per subject, so the access gained is whatever that service account holds, plus any endpoint gated only on being authenticated.
Users of apache-airflow-providers-keycloak are recommended to upgrade to version 0.10.0 or later, which accepts only the configured client on that grant.
Weakness: CWE-287
Which versions are affected by CVE-2026-76187?
It affects 1 product.
Products include Apache Apache-Airflow-Providers-Keycloak.
How do I fix CVE-2026-76187?
No fix has been published for CVE-2026-76187 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-76187 being exploited?
There is no known exploitation of CVE-2026-76187 in the wild and no public exploit code.
Other vulnerabilities in Apache Airflow Keycloak provider
Sources
Also known as GHSA-rwpr-5hxh-f9cm.