Vulnerability Report

CVE-2026-59243

Title: Azure AD OAuth Bypass in FAB Auth Manager

Auth Bypass

Proof Of Concept

PoC Available for CVE-2026-59243

CWE Category CWE-347

Published Date Jul 29, 2026

Modified Date Aug 05, 2026

Exploit Status Available

Score 9.8 CVSS v

Exploit Probability (EPSS)

0.68%

Vulnerability Summary

CVE-2026-59243: The FAB auth manager's Azure AD OAuth login defaulted `verify_signature=False` when decoding the ID token, so an attacker able to present a forged or unsigned (`alg:none`) ID token to the OAuth callback could bypass authentication and log in as an arbitrary user, including one holding the Admin role (CWE-347). Deployments running the FAB auth manager with the Azure AD OAuth login path under its default configuration are affected; the Authentik path already defaulted to `True`. This issue affects `apache-airflow-providers-fab` before 3.7.3. Users are advised to upgrade to `apache-airflow-providers-fab` 3.7.3, which defaults `verify_signature=True`.

Impacted Vendors

apache 1

Reference Links

https://github.com/apache/airflow/pull/69374 https://lists.apache.org/thread/x4784l7z00tl3gw4tv2dmvoon77rxgpl http://www.openwall.com/lists/oss-security/2026/07/28/10

CVSS v3.1

Source Entity 134c704f-9b21-4f2e-91b3-4a467353bcc0

Severity CRITICAL

9.8

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

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

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-59243 Exploits & PoCs (Proof Of Concept)

GitHub https://github.com/0xdak/CVE-2026-59243_exploit

View Code

August 05, 2026 MODIFIED

Vulnerability data updated via NVD.

July 30, 2026 MODIFIED

Vulnerability data updated via NVD.

July 29, 2026 MODIFIED

Vulnerability data updated via NVD.

July 29, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


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

Affected Stack

No specific products linked.