{"id":"CVE-2026-42221","revision":"aeee246b22c14ebf97238a533fbe7087","records":[{"revision":"aeee246b22c14ebf97238a533fbe7087","observedAt":"2026-10-27T11:12:01.124+00:00","statement":{"source":"nvd","id":"CVE-2026-42221","aliases":[],"title":"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 w…","description":"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.","state":0,"publishedAt":"2026-05-04T21:16:32.023+00:00","modifiedAt":"2026-10-26T19:10:00.163+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1,"severity":"HIGH"},{"system":"CVSS 3.1 · nvd@nist.gov · Primary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8,"severity":"CRITICAL"}],"references":["https://github.com/0xJacky/nginx-ui/releases/tag/v2.3.8","https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-h27v-ph7w-m9fp"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-42221","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Analyzed","weaknesses":["CWE-306"],"productCriteria":["cpe:2.3:a:nginxui:nginx_ui:*:*:*:*:*:*:*:*"],"sourceDates":{"published":"2026-05-04T21:16:32.023","lastModified":"2026-10-26T19:10:00.163"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-42221","identifiers":["CVE-2026-42221"]},"retained":false,"historicalAffected":[]}],"coverage":[]}