{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "3.7.3"
              },
              {
                "fixed": "3.8.1"
              },
              {
                "fixed": "3.8.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "DESCRIPTION"
            ]
          },
          "events": [
            {
              "introduced": "21990ed8943ee4dc6e060ee2f11648490c714a3b"
            },
            {
              "fixed": "34500f3a2fa4652272bc831e3c18fd2a6a2da5ef"
            }
          ],
          "repo": "https://github.com/apache/airflow",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "apache",
    "cwe_ids": [
      "CWE-346"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75156.json"
  },
  "details": "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.\n\nThe 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.",
  "id": "CVE-2026-75156",
  "modified": "2026-09-10T03:30:26.507946628Z",
  "published": "2026-09-08T16:47:48.290Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://pypi.python.org"
    },
    {
      "type": "WEB",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-59243"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75156.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://lists.apache.org/thread/n3l6z4jfdxj4p0t8l7m6olkq6xsc6f76"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-75156"
    },
    {
      "type": "FIX",
      "url": "https://github.com/apache/airflow/pull/71735"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Apache Airflow FAB provider: FAB Azure AD OAuth: id_token issuer/audience not validated — cross-tenant authentication bypass"
}