9.8
CRITICAL CVSS 3.1
CVE-2026-27944
Nginx UI: Unauthenticated Backup Download with Encryption Key Disclosure
Description

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.

INFO

Published Date :

March 5, 2026, 7:16 p.m.

Last Modified :

March 5, 2026, 7:38 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-27944 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL [email protected]
Solution
Update Nginx UI to version 2.3.3 or later to patch the authentication bypass and backup disclosure vulnerability.
  • Update Nginx UI to version 2.3.3 or higher.
  • Apply vendor-provided patches for Nginx UI.
  • Remove unneeded API endpoints.
  • Restrict access to sensitive endpoints.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-27944.

URL Resource
https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-g9w5-qffc-6762
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-27944 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-27944 weaknesses.

CAPEC-12: Choosing Message Identifier Choosing Message Identifier CAPEC-36: Using Unpublished Interfaces or Functionality Using Unpublished Interfaces or Functionality CAPEC-62: Cross Site Request Forgery Cross Site Request Forgery CAPEC-166: Force the System to Reset Values Force the System to Reset Values CAPEC-216: Communication Channel Manipulation Communication Channel Manipulation CAPEC-31: Accessing/Intercepting/Modifying HTTP Cookies Accessing/Intercepting/Modifying HTTP Cookies CAPEC-37: Retrieve Embedded Sensitive Data Retrieve Embedded Sensitive Data CAPEC-65: Sniff Application Code Sniff Application Code CAPEC-157: Sniffing Attacks Sniffing Attacks CAPEC-158: Sniffing Network Traffic Sniffing Network Traffic CAPEC-204: Lifting Sensitive Data Embedded in Cache Lifting Sensitive Data Embedded in Cache CAPEC-383: Harvesting Information via API Event Monitoring Harvesting Information via API Event Monitoring CAPEC-384: Application API Message Manipulation via Man-in-the-Middle Application API Message Manipulation via Man-in-the-Middle CAPEC-385: Transaction or Event Tampering via Application API Manipulation Transaction or Event Tampering via Application API Manipulation CAPEC-386: Application API Navigation Remapping Application API Navigation Remapping CAPEC-387: Navigation Remapping To Propagate Malicious Content Navigation Remapping To Propagate Malicious Content CAPEC-388: Application API Button Hijacking Application API Button Hijacking CAPEC-477: Signature Spoofing by Mixing Signed and Unsigned Content Signature Spoofing by Mixing Signed and Unsigned Content CAPEC-609: Cellular Traffic Intercept Cellular Traffic Intercept

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-27944 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-27944 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Mar. 05, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-306
    Added CWE CWE-311
    Added Reference https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-g9w5-qffc-6762
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact