{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-42221",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-04-25T05:04:37.029Z",
        "datePublished": "2026-05-04T20:09:37.308Z",
        "dateUpdated": "2026-05-05T14:14:11.906Z"
    },
    "containers": {
        "cna": {
            "title": "nginx-ui: Unauthenticated First-Run Installer Allows Remote Initial Admin Claim",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-306",
                            "lang": "en",
                            "description": "CWE-306: Missing Authentication for Critical Function",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 8.1,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-h27v-ph7w-m9fp",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-h27v-ph7w-m9fp"
                },
                {
                    "name": "https://github.com/0xJacky/nginx-ui/releases/tag/v2.3.8",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/0xJacky/nginx-ui/releases/tag/v2.3.8"
                }
            ],
            "affected": [
                {
                    "vendor": "0xJacky",
                    "product": "nginx-ui",
                    "versions": [
                        {
                            "version": ">= 2.0.0, < 2.3.8",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-05-04T20:09:37.308Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Nginx UI is a web user interface for the Nginx web server. From version 2.0.0 to before version 2.3.8, an unauthenticated network attacker can claim the initial administrator account on a fresh nginx-ui instance during the first-run setup window. The public /api/install endpoint is reachable without authentication, and the request-encryption flow only protects payload confidentiality in transit; it does not authenticate who is allowed to perform installation. A remote attacker who reaches the service before the legitimate operator can set the admin email, username, and password, causing permanent initial-instance takeover. This issue has been patched in version 2.3.8."
                }
            ],
            "source": {
                "advisory": "GHSA-h27v-ph7w-m9fp",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-h27v-ph7w-m9fp",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-05-05T14:06:26.362325Z",
                                "id": "CVE-2026-42221",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-05-05T14:14:11.906Z"
                }
            }
        ]
    }
}