Vulnerability · Published Mar 5, 2026 · Assigned by GitHub_M
CVE-2026-27944Nginx UI: Unauthenticated Backup Download with Encryption Key Disclosure
Critical 9.8
In plain English
A critical-severity missing authentication in nginx-ui from 0xJacky. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 22.8% (higher than 98% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/0xJacky/Nginx-UI | 2.3.3 | GHSA-g9w5-qffc-6762 |
| Go | github.com/0xJacky/Nginx-UI | no fix listed | GO-2026-4614 |
Affected products (as reported)
Weakness: CWE-311, CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-g9w5-qffc-6762 x_refsource_CONFIRM