CVE-2026-84319 · GHSA-5r62-gj48-897x
Nginx UI: MCP configuration tools bypass restricted directive validation and allow secondary authenticated users to execute NJS in Nginx worker context
- Risk score
- 64/100
- CVSS
- 8.3 v3.1
- Exploit chance (30 days)
- 0.3%
- Published
- 12 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, the regular HTTP configuration API rejects restricted Nginx directives such as load_module, js_import, and js_content. However, the MCP configuration interface allows a secondary authenticated user to write and apply equivalent restricted confi…
- Affected
- github.com/0xJacky/Nginx-UI (go) < 1.9.10-0.20260703131214-23d1934099b0
- Fix
- Upgrade github.com/0xJacky/Nginx-UI to 1.9.10-0.20260703131214-23d1934099b0 or later.
- Exploitation
- No known exploitation
Story map
At a glance
github.com/0xJacky/Nginx-UI: Amber, patch this week. Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, config.ValidateConfigDirectives splits configuration by newline and checks only the first directive token on each line even though Nginx permits multiple semicolon-separated directives on one line. An authenticated caller can place a benign dir…
The flaws
- CVE-2026-84319: Nginx UI: MCP configuration tools bypass restricted directive validation and allow secondary authenticated users to execute NJS in Nginx worker context (CVSS 8.3 · EPSS 0%)
- CVE-2026-84316: Nginx UI: nginx config directive denylist (ValidateConfigFile) is bypassable via same-line ";" separation → authenticated directive injection (RCE on the official image) (CVSS 8.8 · EPSS 0%)
- CVE-2026-84317: Nginx UI: MCP nginx_config_add skips config directive validation → authenticated nginx directive injection (RCE on the official image) (CVSS 8.8 · EPSS 0%)
- CVE-2026-84318: Nginx UI: MCP `nginx_config_add` Bypasses Directive Validation — Authenticated RCE (CVSS 8.8 · EPSS 1%)
The fix
Upgrade github.com/0xJacky/Nginx-UI: 2.4.1 or later on your release line
Who is exposed: github.com/0xJacky/Nginx-UI (go) < 1.9.10-0.20260703131214-23d1934099b0
Where it stands
- Public proof of concept
Connects to
- Same weakness: CWE-693 (CWE-693). 58 other warnings in 30 days
Why it is Amber
- CVSS 8.3 high
- On your watchlist: nginx, Go
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| github.com/0xJacky/Nginx-UI | go | < 1.9.10-0.20260703131214-23d1934099b0 | 1.9.10-0.20260703131214-23d1934099b0 |
References
- https://github.com/advisories/GHSA-5r62-gj48-897x
- https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-5r62-gj48-897x
- https://nvd.nist.gov/vuln/detail/CVE-2026-84319
- https://github.com/0xJacky/nginx-ui/commit/23d1934099b05b2a01589b48129dc3d3159d91c2
- https://github.com/0xJacky/nginx-ui/releases/tag/v2.4.1
- https://github.com/advisories/GHSA-5r62-gj48-897x
Original description
Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, the regular HTTP configuration API rejects restricted Nginx directives such as load_module, js_import, and js_content. However, the MCP configuration interface allows a secondary authenticated user to write and apply equivalent restricted configuration content. This allows the user to load ngx_http_js_module.so, import attacker-controlled JavaScript, reload Nginx, and execute NJS in the Nginx worker context. This issue is fixed in version 2.4.1.
Last activity 12 Oct 2026. Patch Forecast updates every hour.