CVE-2026-27944criticalobserved exploitationCWE-306CWE-311

CVE-2026-27944: critical vulnerability in 0xJacky nginx-ui

Nginx UI: Unauthenticated Backup Download with Encryption Key Disclosure

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90Vexday Risk Score

Patch now. It exploitation observed by VulnCheck and has a working public exploit.

ssvc Actcvss 9.8epss 23%
from disclosure to weapon5 days
Published on NVDMar 5
1st PoC+5d
VulnCheck+14d
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
0xJacky · nginx-ui
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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