← Vulnerability feed

Vulnerability record · CVE-2026-76187 · published 16 September 2026

CVE-2026-76187: Apache-airflow-providers-keycloak improper authentication vulnerability

Apache · Apache Airflow Providers Keycloak

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.

9.8 CVSS 3.1 Critical EPSS 0.98% · top 39.4% CWE-287 · Improper authentication
9.8CVSS 3.1 base score
0.98%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
18 Sep 2026Last modified by NVD

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.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/apache/airflow/pull/72205 PatchVendor Advisory
https://lists.apache.org/thread/5cqh5ojl3718ogb0q1dcd9vdr47z7gp3 Mailing List
https://lists.apache.org/thread/[email protected] Mailing List
http://www.openwall.com/lists/oss-security/2026/09/15/9 Third Party Advisory

Track CVE-2026-76187 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.1CVE-2026-76186Apache-airflow-providers-keycloak reliance on cookies without validation vulnerabilityApache Airflow Keycloak provider: from Airflow 3.3 the Keycloak auth manager takes a user's identity from the signed Airflow session token but takes …EPSS 0.81%5.4CVE-2026-40948Apache-airflow-providers-keycloak cross-site request forgery vulnerabilityThe Keycloak authentication manager in `apache-airflow-providers-keycloak` did not generate or validate the OAuth 2.0 `state` parameter on the login …EPSS 0.36%7.5CVE-2026-42018JFrog Artifactory improper authentication leaks anonymous tokenJFrog Artifactory can return an internal anonymous-user token to an unauthenticated caller even when anonymous access is disabled. Because the token …KEVEPSS 9.8%analysed9.8CVE-2026-82329JFrog Artifactory improper authentication allows admin takeoverJFrog Artifactory contains an improper authentication weakness (CWE-287) that, under default configuration, may let an unauthenticated attacker with …KEVEPSS 14%analysed8.8CVE-2026-59822LiteLLM MCP endpoint auth bypass via OAuth2 passthrough fallbackLiteLLM's MCP Streamable HTTP endpoint, prior to 1.84.0, let an unauthenticated attacker send a fabricated Authorization header that triggered an OAu…KEVEPSS 0.84%analysed10.0CVE-2026-49869Kestra OSS auth bypass via path suffix match enables RCEKestra OSS AuthenticationFilter whitelists the public config endpoint using request.getPath().endsWith("/configs"), a suffix match instead of an exac…KEVEPSS 2.1%analysed9.8CVE-2023-49105ownCloud Server WebDAV authentication bypass via pre-signed URLsownCloud core before 10.13.1 accepts pre-signed URLs even when the file owner has no signing-key configured, so the signature check is effectively sk…KEVEPSS 43%analysed9.8CVE-2026-65400Apple macOS Screen Sharing authentication bypassAn improper authentication flaw in Apple macOS Screen Sharing allows a network attacker to authenticate without valid credentials. Apple fixed it via…KEVEPSS 1.2%analysed

Source: NIST National Vulnerability Database (record CVE-2026-76187), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.