Vulnerability in Apache Apache-Airflow-Providers-Keycloak

CVE-2026-76186

Apache Airflow Keycloak provider: from Airflow 3.3 the Keycloak auth manager takes a user's identity from the signed Airflow session token but takes the Keycloak access and refresh tokens used for every authorization decision from separate, unauthenticated cookies, and never checks that the two describe the same subject. A user who holds any valid Airflow login of their own, together with another subject's Keycloak access or refresh token obtained out of band, can pair the two: Airflow then authorizes requests with the foreign token's privileges while the session identity, audit log and cache keys continue to name the attacker's own account. The refresh path re-issues an Airflow session token for the original identity carrying the foreign tokens, so the mismatched pairing survives across sessions. Affects deployments running Airflow 3.3 or later with the Keycloak auth manager. Earlier versions carried the Keycloak tokens inside the signed session token, so the binding existed and was lost when they moved into separate cookies. Users of apache-airflow-providers-keycloak are recommended to upgrade to version 0.10.0 or later, which binds the cookie-supplied tokens to the session identity.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.008 (56.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-76186: held from 0.008 to 0.008.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-76186?
CVE-2026-76186 is a critical-severity vulnerability in Apache Apache-Airflow-Providers-Keycloak, classified under Reliance on Cookies without Validation and Integrity Checking. CVSS score: 9.1/10. Published 2026-09-16.
How severe is CVE-2026-76186?
Critical severity. CVSS v3 base score is 9.1 out of 10.