{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "2FAuth",
          "vendor": "Bubka",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 8.0.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "2FAuth is a web app to manage Two-Factor Authentication (2FA) accounts and generate their security codes. Prior to 8.0.0, when AUTHENTICATION_GUARD=reverse-proxy-guard accepts authentication headers from a client that did not pass through a trusted proxy, RemoteUserProvider::retrieveById() creates an account for an unknown REMOTE_USER, promotes the first created account to administrator, and synchronizes the account email from the configured mail header. An unauthenticated remote client can therefore create an administrator on a fresh instance or impersonate and redirect email for a known account, exposing 2FA secrets and administrative functions. This issue is fixed in version 8.0.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-287",
              "description": "CWE-287: Improper Authentication",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-06T20:20:27.407Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/Bubka/2FAuth/security/advisories/GHSA-r9xx-45m8-mw24",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/Bubka/2FAuth/security/advisories/GHSA-r9xx-45m8-mw24"
        },
        {
          "name": "https://github.com/Bubka/2FAuth/commit/43873cbfba445926c7008b4291eeee67752af9e8",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/Bubka/2FAuth/commit/43873cbfba445926c7008b4291eeee67752af9e8"
        },
        {
          "name": "https://github.com/Bubka/2FAuth/commit/8a4c395cac97f8b70b4a822639a6ad8a816f927c",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/Bubka/2FAuth/commit/8a4c395cac97f8b70b4a822639a6ad8a816f927c"
        },
        {
          "name": "https://github.com/Bubka/2FAuth/commit/d9e58ac4a63fbd8a073e423567881c81a87915de",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/Bubka/2FAuth/commit/d9e58ac4a63fbd8a073e423567881c81a87915de"
        },
        {
          "name": "https://github.com/Bubka/2FAuth/releases/tag/v8.0.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/Bubka/2FAuth/releases/tag/v8.0.0"
        }
      ],
      "source": {
        "advisory": "GHSA-r9xx-45m8-mw24",
        "discovery": "UNKNOWN"
      },
      "title": "2FAuth: Reverse Proxy Guard Auto-Creates Users With Admin Promotion From Unauthenticated Header Value"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-63438",
    "datePublished": "2026-11-06T20:20:27.407Z",
    "dateReserved": "2026-07-16T19:35:57.767Z",
    "dateUpdated": "2026-11-06T20:20:27.407Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}