The Apache Airflow FAB provider fails to verify Azure AD OAuth ID token signatures, allowing unauthenticated attackers to bypass authentication and ga...
Description
The Apache Airflow FAB provider fails to verify Azure AD OAuth ID token signatures, allowing unauthenticated attackers to bypass authentication and gain administrative access via forged tokens.
AI Analyst Comment
Remediation
Update Apache Software Foundation Apache Airflow FAB provider to the latest version. Check the vendor security advisory for specific patch details. Monitor for exploitation attempts and review access logs.
---METADATA---
VENDOR: Apache Software Foundation
PRODUCT: Apache Airflow FAB provider
AFFECTED_VERSIONS: 0 up to (excluding) 3.7.3
CONFIDENCE: high
MISSING: none
---END_METADATA---
Description Summary:
The Apache Airflow FAB provider fails to verify Azure AD OAuth ID token signatures, allowing unauthenticated attackers to bypass authentication and gain administrative access via forged tokens.
Executive Summary:
A critical authentication bypass vulnerability in the Apache Airflow FAB provider allows unauthenticated attackers to gain full administrative control over the application.
Vulnerability Details
CVE-ID: CVE-2026-59243
Affected Software: Apache Software Foundation Apache Airflow FAB provider
Affected Versions: 0 up to (excluding) 3.7.3
Vulnerability: This vulnerability involves the improper verification of cryptographic signatures (CWE-347) within the FAB auth manager. An unauthenticated attacker can present a forged ID token to the OAuth callback, resulting in successful authentication as an arbitrary user, including those with administrative privileges.
Business Impact
The potential for unauthorized administrative access poses a catastrophic risk to organizational data and system integrity. Because this flaw allows for full account takeover without valid credentials, attackers could exfiltrate sensitive workflow data, modify system configurations, or deploy malicious tasks. The CVSS score of 9.8 reflects the high probability of exploitation and the severe impact on confidentiality, integrity, and availability.
Remediation Plan
Immediate Action: Upgrade to
apache-airflow-providers-fabversion 3.7.3 or later, which correctly enforces ID token signature verification.Proactive Monitoring: Review authentication logs for unusual login patterns, specifically focusing on OAuth callbacks that originate from unexpected sources or contain suspicious token signatures.
Compensating Controls: Implement strict network access controls to limit exposure of the Airflow management interface to trusted internal networks only, reducing the attack surface for remote exploitation.
Exploitation Status
Public Exploit Available: Yes, a public proof-of-concept exists on GitHub.
Analyst Notes: As of July 29, 2026, there is no confirmed active exploitation in the wild; however, per CISA's SSVC assessment a proof-of-concept exists, so exploitation risk should be treated as credible. The flaw is inherently dangerous due to the ease of bypassing authentication via simple token manipulation.
Analyst Recommendation
Given the critical severity and the availability of a public proof-of-concept, organizations must prioritize upgrading the Apache Airflow FAB provider. Failure to patch allows trivial, unauthenticated access to the entire Airflow environment, which should be mitigated immediately to prevent potential compromise.