Auth bypass grants admin access in Apache Airflow, a widely used data platform; high-impact across organizations and must be acted on immediately.
CVE-2026-59243
Auth bypass in Airflow FAB Azure AD OAuth allows login as any user.
Is CVE-2026-59243 being exploited?
Not confirmed. CVE-2026-59243 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.45% probability of exploitation in the next 30 days.
How severe is CVE-2026-59243?
CVE-2026-59243 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-59243?
Yes. A fix has been recorded for CVE-2026-59243. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-59243 affect?
CVE-2026-59243 affects apache-airflow-providers-fab < 3.7.3, Airflow deployments using FAB Azure AD OAuth login with default settings. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-59243?
Upgrade apache-airflow-providers-fab to 3.7.3 immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Attackers can present forged/unsigned Azure AD ID tokens to bypass auth and log in as arbitrary users, including Admins.
Immediate action required
- affected< 3.7.3
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.