0.0
NA
CVE-2026-59243
Apache Airflow FAB provider: FAB auth manager: JWT signature verification disabled by default for Azure AD OAuth (`verify_signature` defaults to `False`)
Description

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`.

INFO

Published Date :

July 29, 2026, 10:16 a.m.

Last Modified :

July 29, 2026, 10:16 a.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-59243 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Upgrade the FAB auth manager to version 3.7.3 to ensure ID token signature verification is enabled.
  • Upgrade apache-airflow-providers-fab to version 3.7.3.
  • Ensure verify_signature is set to True.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-59243.

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

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-59243 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-59243 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-59243 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-59243 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 29, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Apache Software Foundation', 'product': 'Apache Airflow FAB provider', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.7.3', 'versionType': 'semver'}], 'packageName': 'apache-airflow-providers-fab', 'collectionURL': 'https://pypi.python.org', 'defaultStatus': 'unaffected'}]
    Added Description 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`.
    Added CWE CWE-347
    Added Reference https://github.com/apache/airflow/pull/69374
    Added Reference https://lists.apache.org/thread/x4784l7z00tl3gw4tv2dmvoon77rxgpl
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Jul. 29, 2026

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2026/07/28/10
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.