CVE-2026-27944 Scanner

Nginx UI is primarily used by server administrators and developers to manage Nginx web server configurations with a graphical user interface. It is employed in various environments to simplify the configuration process and streamline web server management tasks. This software is used in corporate settings for managing internal and client-facing web services effectively. Its primary audience includes IT professionals seeking a user-friendly interface for configuration tasks. The product is beneficial for reducing the complexity associated with manual Nginx configuration management. Additionally, Nginx UI aids in deploying, monitoring, and scaling web services in a networked environment.

An information disclosure vulnerability exists in Nginx UI versions below 2.3.3. This vulnerability allows unauthenticated access to sensitive information due to inadequate access control mechanisms. Unauthenticated attackers can retrieve encryption keys by accessing the /api/backup endpoint. The vulnerability results from the exposure of encryption keys through the X-Backup-Security header. Exploitation is straightforward due to the lack of authentication required to access the vulnerable endpoint. The vulnerability poses a significant threat, particularly in environments where sensitive information is stored in system backups.

The vulnerable endpoint in Nginx UI is the /api/backup path, which can be accessed with a simple HTTP GET request. The issue arises from the improper handling of sensitive headers, allowing encryption keys to be exposed to unauthorized parties. In particular, the X-Backup-Security header is susceptible to unauthorized disclosure. Technical aspects of the vulnerability include the failure to enforce authentication on certain endpoints, thus exposing sensitive data. The vulnerability is exploited by sending requests to retrieve backup files, which may include critical information. The presence of the 'X-Backup-Security' header indicates the vulnerability is present.

Exploitation of this vulnerability can lead to unauthorized decryption of full system backups. Attackers can gain access to sensitive data, including credentials and private keys, which can be used for further attacks. Organizations may face severe data breaches leading to the loss of confidential information. The exploitation could facilitate unauthorized access to systems and services if encryption keys are used for other purposes. Furthermore, reputational damage and financial loss could occur due to the exposure of sensitive internal communications. To mitigate potential impacts, organizations should promptly address this vulnerability by updating to the latest version of the product.

REFERENCES

• https://github.com/advisories/GHSA-g9w5-qffc-6762
• https://www.tenable.com/security/research/tra-2026-17
• https://vulnerabletarget.com/VT-2026-27944