# CVE-2026-84320: Nginx UI auto backup path traversal in storage boundary

Source: https://junglewise.ai/threats/cve-2026-84320-nginx-ui-auto-backup-name-allows-path-traversal-outside-validated  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-12. Updated: 2026-10-15  
License: CC BY 4.0 with a link back

CVE-2026-84320 · Severity: medium · CVSS 6.3 · Published 2026-10-12

Nginx UI, a web-based configuration management tool for Nginx, enforces a security boundary to restrict backup file storage to administrator-approved directories. However, an authenticated user can create backup tasks with names containing path traversal sequences (such as `../../../`) that bypass this boundary and write backup files outside the intended storage directory. Backups may contain sensitive Nginx configuration, databases, and encryption keys, potentially exposing them in unauthorized locations.

Technologies: [github.com/0xJacky/Nginx-UI (Go)](https://junglewise.ai/threats/technologies/github-com-0xjacky-nginx-ui), [Nginx UI](https://junglewise.ai/threats/technologies/nginx-ui-nginx-ui). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Nginx UI](https://junglewise.ai/threats/vendors/nginx-ui).

## Quick answers

**Is CVE-2026-84320 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-84320 being exploited in the wild.

**How severe is CVE-2026-84320?** Medium severity, with a CVSS score of 6.3, published 12 October 2026.

**Which products and versions are affected?** github.com/0xJacky/Nginx-UI (Go) < 1.9.10-0.20260715121709-f92218e01054, SEMVER:introduced=0,fixed=1.9.10-0.20260715121709-f92218e01054; Nginx UI v2.3.10 and dev branch (commit 4948fba8744e82c3d7003f68ee164e9f49421066).

**Is there a fix for CVE-2026-84320?** Yes. github.com/0xJacky/Nginx-UI (Go): upgrade to 1.9.10-0.20260715121709-f92218e01054 or later. Until then: Reject path separators (`/`, `\`), parent directory references (`..`), and NUL bytes in auto-backup task names through input validation. Additionally, after constructing the final output path, verify that the cleaned path remains within the validated `storage_path` boundary before writing the backup file. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-84320 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-84320?** Check whether you run github.com/0xJacky/Nginx-UI (Go) or Nginx UI at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/0xJacky/Nginx-UI (Go): upgrade to 1.9.10-0.20260715121709-f92218e01054 or later

  ```sh
  go get github.com/0xJacky/Nginx-UI@v1.9.10-0.20260715121709-f92218e01054
  ```


Reject path separators (`/`, `\`), parent directory references (`..`), and NUL bytes in auto-backup task names through input validation. Additionally, after constructing the final output path, verify that the cleaned path remains within the validated `storage_path` boundary before writing the backup file.

## Technical details

The vulnerability is a path traversal flaw in the auto-backup filename construction. The `AutoBackup.GetName()` method only trims whitespace and spaces but does not sanitize path separators or traversal sequences; when combined with `filepath.Join(storage_path, filename)`, this allows an authenticated attacker to embed `../` components in the backup name that escape the validated storage directory. The root cause is that `storage_path` validation passes but the final output path after appending the unsanitized backup name is never validated against the `GrantedAccessPath` boundary. This enables writing backup archives and associated key files outside the intended directory with the Nginx UI process privileges.

## Affected products

- Nginx UI Nginx UI v2.3.10 and dev branch (commit 4948fba8744e82c3d7003f68ee164e9f49421066)

## Identifiers

- CVE-2026-84320
- GHSA-jrq7-xrjx-pcfw
- GO-2026-6788

## Timeline

- 2026-10-15: disclosed

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