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.
Affected products
nginxui: nginx ui
References3
- github.com/0xJacky/nginx-ui/security/advisories/GHSA-h27v-ph7w-… ExploitMitigationVendor Advisory
- github.com/0xJacky/nginx-ui/security/advisories/GHSA-h27v-ph7w-… ExploitMitigationVendor Advisory
- github.com/0xJacky/nginx-ui/releases/tag/v2.3.8 Release Notes
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 72 · as of 13 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
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