CVE-2026-84320
6.3MediumPublished 12 Oct 2026 · NVD status: Deferred · AI triage by gemini-3.8-flash
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Impact
- Limited impact
- Weakness
- CWE-22
Impact
Authenticated attackers can write arbitrary backup archives and encryption keys outside the intended directory with the privileges of the Nginx UI process. They need a valid user account that can create or edit automatic backups.
Root cause
AutoBackup.GetName fails to sanitize path separators and parent-directory components from user-supplied names before passing them to filepath.Join.
Affected systems
Nginx UI prior to 2.4.3
CVSS v3.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Fix & remediation
Upgrade Nginx UI to version 2.4.3 or later. If upgrading immediately is not possible, restrict or revoke permissions for untrusted users to create or modify automatic backups.
AI-suggested. Run it in staging first and check it against the vendor advisory. Why?
NVD description
Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.3, Nginx UI validates an automatic backup's storage_path, but AutoBackup.GetName returns a user-controlled name without rejecting path separators or parent-directory components, and downstream filename formatting embeds that result in the final archive filename. An authenticated user who can create or modify an automatic backup can cause filepath.Join to resolve the generated archive path outside the validated storage directory, allowing backup archives to be written with the Nginx UI process privileges. For encrypted configuration backups, the adjacent encryption key file can also be written outside the validated directory. This issue is fixed in version 2.4.3.