CVE-2026-84317

8.8 HIGH 0.5% exploit odds Fix listed Other Library

What it is

Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, internal/config/validation.go (ValidateConfigFile) is a security control that blocks dangerous nginx directives — js_*, perl_*, load_module of the njs/perl modules, and user root. It is enforced on three of the four config-write paths: api/config/add.go, api/config/modify.go, and mcp/config/config_modify.go. The fourth path — the MCP tool nginx_config_add (mcp/config/config_add.go) — does NOT call it: it writes the caller-supplied content straight to disk and reloads nginx. An authenticated MCP caller (or an MCP agent induced via prompt injection) can therefore inject exactly the directives the control is meant to block, leading to nginx code execution on deployments where the njs/perl module is available (e.g. the official Docker image). This issue is fixed in version 2.4.1.

At a glance

Exploitability: Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering, service disruption.
Exploit odds: 0.5% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-09-01 16:17 UTC ReservedThe CVE id was reserved by its CNA
2026-10-12 21:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-10-13 18:17 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 0.5% in the next 30 days (EPSS).
Severity: 8.8 HIGH (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2026-10-12 21:17 UTC
Last modified: 2026-10-13 18:17 UTC
Exploit probability: 0.5% · EPSS, next 30 days
Weakness: CWE-20 · Improper input validation
Record status: Deferred

Attack profile CVSS 3.1 · 8.8

Attack vector: Network
Complexity: Low
Privileges needed: Low
User interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Raw vector

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

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-84317.md and follow it. Check whether this project is affected by CVE-2026-84317. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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Fix and advisories

References

NVD record · CVE.org record