CVE-2026-27944

Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.3, the /api/backup endpoint is accessible without authentication and discloses the encryption keys required to decrypt the backup in the X-Backup-Security response header. This allows an unauthenticated attacker to download a full system backup containing sensitive data (user credentials, session tokens, SSL private keys, Nginx configurations) and decrypt it immediately. This issue has been patched in version 2.3.3.

Affected products

Nginx-Ui

Nginxui Nginx Ui

< 2.3.3

Fix

Available

CVSS 3.1

9.8 CRITICAL

EPSS

22.2% (97th percentile)

Weakness

CWE-311, CWE-306

NVD status

Analyzed

Published

2026-03-05