CVE-2026-42238
CriticalSummary
Nginx UI, a web user interface for the Nginx web server, prior to version 2.3.8, exposed a backup restore endpoint (POST /api/restore) that was completely unauthenticated during the first 10 minutes after process startup on any fresh installation. An unauthenticated remote attacker could upload a crafted backup archive that overwrote the application's configuration file and SQLite database.
Risk Assessment
An attacker could inject arbitrary OS commands, posing a serious security risk, especially when the application runs with root privileges. This could lead to full system compromise.
Recommendation
It is recommended to update Nginx UI to version 2.3.8 or later to mitigate this vulnerability. Additionally, consider restricting access to the backup restore endpoint.
Other vulnerabilities in Nginx UI
See all- CVE-2026-44015High
Nginx UI is a web user interface for the Nginx web server. In versions 2.3.4 and earlier, an authenticated user can perform Server-Side Request Forgery (SSRF) by creating a cluster node pointing to an arbitrary internal URL.
- CVE-2026-42222High
In version 2.3.5 of the Nginx user interface (nginx-ui), there is an unauthenticated bootstrap takeover vulnerability during the initial installation exposed by POST /api/install.
- CVE-2026-42221High
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.
Original NVD description (English source)
Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.8, nginx-ui exposes a backup restore endpoint (POST /api/restore) that is completely unauthenticated during the first 10 minutes after process startup on any fresh installation. An unauthenticated remote attacker can upload a crafted backup archive that overwrites the application's configuration file (app.ini) and SQLite database. Because the attacker controls the restored app.ini, they can inject an arbitrary OS command into the TestConfigCmd setting. After the application automatically restarts to apply the restored config, a single follow-up request triggers that command as the user running nginx-ui — typically root in Docker deployments. This issue has been patched in version 2.3.8.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

