{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f6b4beed26b55d02a81fb064b0a21fb059aa99fe"
            },
            {
              "fixed": "9079a98b44beb1c4e77215a262b95e6fd44c1dfb"
            }
          ],
          "repo": "https://github.com/himmelblau-idm/himmelblau",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-q746-m2wv-qh4v"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-1188"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31957.json"
  },
  "details": "Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. From 3.0.0 to before 3.1.0, if Himmelblau is deployed without a configured tenant domain in himmelblau.conf, authentication is not tenant-scoped. In this mode, Himmelblau can accept authentication attempts for arbitrary Entra ID domains by dynamically registering providers at runtime. This behavior is intended for initial/local bootstrap scenarios, but it can create risk in remote authentication environments. This vulnerability is fixed in 3.1.0.",
  "id": "CVE-2026-31957",
  "modified": "2026-04-01T23:10:16.237505621Z",
  "published": "2026-03-11T19:25:21.230Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31957.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/himmelblau-idm/himmelblau/security/advisories/GHSA-q746-m2wv-qh4v"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31957"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Himmelblau unset domain configuration can allow any-tenant authentication at first login for remote deployments"
}