CVE-2026-84320
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.
Does this matter?
Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 6.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
- EPSS
- 0.17% probability · 6th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- security-advisories@github.com
EPSS moved from 0.2% on 13 October 2026 to 0.2% on 26 October 2026.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.