Medium severity · published Oct 12, 2026
CVE-2026-84320
Nginx UI: Auto backup name allows path traversal outside validated storage path
6.3
CVSS
0.2%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NG
nginx-ui · 0xJacky
< 2.4.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84320
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-84320
x_refsource_CONFIRM
https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-jrq7-xrjx-pcfw
x_refsource_MISC
https://github.com/0xJacky/nginx-ui/commit/f92218e01054491fc1e6684dc6f7facaf8ab41eb
x_refsource_MISC
https://github.com/0xJacky/nginx-ui/releases/tag/v2.4.3
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