---
id: CVE-2026-75156
title: >-
  Apache Airflow FAB provider versions 3.7.3 through 3.8.0 do not validate the
  issuer or audience of Azure AD `id_token`s during OAuth login
summary: >-
  Apache Airflow FAB provider versions 3.7.3 through 3.8.0 do not validate the
  issuer or audience of Azure AD `id_token`s during OAuth login. Deployments are
  affected only when the FAB auth manager is configured with Azure AD as an
  OAuth p…
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-346
vendor: apache
product: apache-airflow-providers-fab
affected:
  - 'apache-airflow-providers-fab >= 3.7.3, < 3.8.1'
patched:
  - apache-airflow-providers-fab 3.8.1
published: '2026-09-08'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T14:25:21.873'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-75156'
references:
  - url: 'https://github.com/apache/airflow/pull/71735'
    label: security@apache.org
  - url: 'https://lists.apache.org/thread/n3l6z4jfdxj4p0t8l7m6olkq6xsc6f76'
    label: security@apache.org
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-59243'
    label: security@apache.org
tags:
  - nvd
  - cve.org
epss: 0.00379
epssPercentile: 0.2911
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-09-08T18:59:35.794768Z'
ingestedAt: '2026-09-08T19:08:49.600Z'
---

## Overview

Apache Airflow FAB provider versions 3.7.3 through 3.8.0 do not validate the issuer or audience of Azure AD `id_token`s during OAuth login. Deployments are affected only when the FAB auth manager is configured with Azure AD as an OAuth provider. Because the signing keys are fetched from Microsoft's **multi-tenant** JWKS endpoint, an `id_token` minted in *any* Azure tenant — including one the attacker creates — passes signature verification, and the username and role assignments are then read from that attacker-controlled token. Anyone able to register an Azure tenant can therefore authenticate to the Airflow UI with no prior access to the deployment.

The fix for **CVE-2026-59243** was incomplete, and this advisory closes the remaining gap: that fix made the provider verify the `id_token` signature, but did not add issuer or audience checks. Operators who already applied the CVE-2026-59243 fix are **still affected and must upgrade again** — 3.7.3 is the release that shipped that fix, so every version containing it falls inside this affected range. Upgrade to apache-airflow-providers-fab `3.8.1` or later.

## Affected

- `apache-airflow-providers-fab >= 3.7.3, < 3.8.1`

## Remediation

Upgrade past the affected range:

- `apache-airflow-providers-fab 3.8.1`