CVE-2026-59243 json
Apache Airflow FAB provider: FAB auth manager: JWT signature verification disabled by default for Azure AD OAuth (`verify_signature` defaults to `False`)
published 2026-07-29 3 mo ago modified 2026-10-23 16 d ago also EUVD-2026-50216
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 51%
- public exploits
- 0
- none known
Summary
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`.
Patch / fix
- Apache Software Foundation Apache Airflow FAB provider 3.7.3
- github.com/apache/airflow#69374 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 3 mo ago
Exploit prediction
0.64% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- Apache Software Foundation Apache Airflow FAB provider
Classification
- Weakness
-
- CWE-347 Improper Verification of Cryptographic Signature
References
-
github.com
/apache/airflow/pull/69374
patch
-
lists.apache.org
/thread/x4784l7z00tl3gw4tv2dmvoon77rxgpl
vendor-advisory, mailing-list
-
openwall.com
/lists/oss-security/2026/07/28/10
mailing-list, third-party-advisory
Sources
- CVE List CVE-2026-59243
- NVD CVE-2026-59243
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