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.
{
"cna_assigner": "apache",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59243.json",
"cwe_ids": [
"CWE-347"
]
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "3.7.3"
}
],
"source": [
"AFFECTED_FIELD",
"CPE_RANGE"
],
"cpe": "cpe:2.3:a:apache:apache-airflow-providers-fab:*:*:*:*:*:*:*:*"
}