9.8

CVE-2026-42221

Exploit

nginx-ui: Unauthenticated First-Run Installer Allows Remote Initial Admin Claim

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
NginxuiNginx Ui Version >= 2.0.0 < 2.3.8
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.35% 0.262
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 9.8 3.9 5.9
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
security-advisories@github.com 8.1 2.2 5.9
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-306 Missing Authentication for Critical Function

The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

https://github.com/0xJacky/nginx-ui/releases/tag/v2.3.8
Release Notes
https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-h27v-ph7w-m9fp
Vendor Advisory
Exploit
Mitigation