Backup for Microsoft 365 — security advisory

{
  "id": "e9e2681493162e856631bae8ef34730a0a0c5a51aecb297cc4ebd07fdea1ba71",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-106078",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-106078",
    "summary": "A vulnerability allowing an unauthenticated attacker to bypass REST API authentication with a forged federation token and receive responses from REST API endpoints that do not call the Veeam Backup for Microsoft 365 backup service.",
    "evidence": "cve:CVE-2026-106078",
    "products": [
      {
        "name": {
          "value": "Backup for Microsoft 365",
          "evidence": "/containers/cna/affected/0/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-106078",
      "aliases": [
        "CVE-2026-106078"
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "version": "4.0",
            "baseScore": 6.9,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
          }
        }
      ],
      "affected": [
        {
          "vendor": "Veeam",
          "product": "Backup for Microsoft 365",
          "versions": [
            {
              "status": "affected",
              "version": "8.0",
              "versionType": "semver",
              "lessThanOrEqual": "8.6.0.1102"
            }
          ],
          "defaultStatus": "unaffected"
        }
      ],
      "modified": "2026-10-27T16:16:58.925Z",
      "provider": "cve",
      "references": [
        "https://www.veeam.com/kb4957"
      ],
      "provider_metadata": {
        "cna": {
          "orgId": "36234546-b8fa-4601-9d6f-f4e334aa8ea1",
          "shortName": "hackerone",
          "dateUpdated": "2026-10-27T16:16:58.925Z"
        }
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-106078",
        "evidence": "/cveMetadata/cveId"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/containers/cna/metrics"
  },
  "source_id": "core-cve",
  "document_id": 394447,
  "published_at": "2026-10-27T16:16:58.925+00:00"
}