Nginx UI: nginx config directive denylist (ValidateConfigFile) is bypassable via same-line ";" separation → authenticated directive injection (RCE on the official image)

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.8 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

• CVE-2026-84316: 0.51% estimated exploitation activity in the next 30 days; percentile 43.32 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary config.ValidateConfigFile is the security control that blocks dangerous nginx directives (js, perl, loadmodule of njs/perl modules, user root). Its directive scanner is bypassable: it splits the config by newlines and inspects only the FIRST token of each line, but nginx separates directives with ;, not newlines. Putting a benign directive first and the blocked directive after a ; on the SAME line defeats every check. The include directive is also not on the denylist. As a result, an authenticated caller can inject the exact directives the hardening was meant to block, through EVERY path that calls the validator — POST /api/configs (add), the REST config modify endpoint (api/config/modify.go), the MCP nginxconfigmodify tool, and the site/stream save paths (internal/site/save.go, internal/stream/save.go). On deployments where nginx has the njs/perl module (the official uozi/nginx-ui Docker image ships ngxhttpjsmodule.so), this leads to code execution in the nginx worker; with…

Published by the source

15 Oct 2026, 20:13 UTC

Last modified by the source

19 Oct 2026, 21:31 UTC

Source last checked

26 Oct 2026, 15:32 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-cf23-7qxj-xmhr

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6782

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-cf23-7qxj-xmhr

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# Patch Next advisory brief: CVE-2026-84316

Advisory: Nginx UI: nginx config directive denylist (ValidateConfigFile) is bypassable via same-line ";" separation → authenticated directive injection (RCE on the official image)
IDs: CVE-2026-84316, GHSA-cf23-7qxj-xmhr
Record: https://patchnext.com/advisories/cve-2026-84316 (revision 3, source checked 26 Oct 2026, 15:32 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/0xJacky/Nginx-UI 1.9.10-0.20260703131214-23d1934099b0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/0xJacky/Nginx-UI: affected < 1.9.10-0.20260703131214-23d1934099b0; fixed in 1.9.10-0.20260703131214-23d1934099b0

## Suggested inspection (read-only)
- Go github.com/0xJacky/Nginx-UI: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/0xJacky/Nginx-UI.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6782 (OSV record GO-2026-6782 lists affected ranges: Go github.com/0xJacky/Nginx-UI >=0 <1.9.10-0.20260703131214-23d1934099b0 (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-cf23-7qxj-xmhr (OSV record GHSA-cf23-7qxj-xmhr lists affected ranges: Go github.com/0xJacky/Nginx-UI >=0 <1.9.10-0.20260703131214-23d1934099b0 (fixed))
- Verified: https://github.com/advisories/GHSA-cf23-7qxj-xmhr (GitHub-reviewed advisory GHSA-cf23-7qxj-xmhr lists affected ranges: Go github.com/0xJacky/Nginx-UI >=0 <1.9.10-0.20260703131214-23d1934099b0)

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