{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-63438",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-07-16T19:35:57.767Z",
        "datePublished": "2026-11-06T20:20:27.407Z",
        "dateUpdated": "2026-11-06T20:20:27.407Z"
    },
    "containers": {
        "cna": {
            "title": "2FAuth: Reverse Proxy Guard Auto-Creates Users With Admin Promotion From Unauthenticated Header Value",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-287",
                            "lang": "en",
                            "description": "CWE-287: Improper Authentication",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "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"
                    }
                }
            ],
            "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"
                }
            ],
            "affected": [
                {
                    "vendor": "Bubka",
                    "product": "2FAuth",
                    "versions": [
                        {
                            "version": "< 8.0.0",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-11-06T20:20:27.407Z"
            },
            "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."
                }
            ],
            "source": {
                "advisory": "GHSA-r9xx-45m8-mw24",
                "discovery": "UNKNOWN"
            }
        }
    }
}