CVE-2026-27944 | Nginx UI is a web user interface for the Nginx web server. P… | CVSS 9.8 CRITICAL

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.

Metadata

CVE ID: CVE-2026-27944
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-02-25 03:11 UTC
Published: 2026-03-05 16:28 UTC
Last updated: 2026-03-19 14:49 UTC
Primary CWE: CWE-311
CWE-311: Missing Encryption of Sensitive Data
Vendor / Product: 0xJacky / nginx-ui
Sources: cve.org · NVD

Severity & Metrics

9.8 CRITICAL CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: yes
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
0xJacky	nginx-ui	—	< 2.3.3

Weakness (CWE)

CWE	Source	Description
CWE-306	cna	CWE-306: Missing Authentication for Critical Function
CWE-311	cna	CWE-311: Missing Encryption of Sensitive Data

CVSS scores (1)

Score	Severity	Version	Source	Vector
9.8	CRITICAL	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References (1)

https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-g9w5-qffc-6762 https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-g9w5-qffc-6762