CVE-2026-84317

Summary

Nginx UI allows authenticated attackers to bypass security controls that block dangerous Nginx directives like js_* and perl_*, enabling arbitrary code execution when the njs/perl modules are available. This affects deployments where the MCP tool is used to modify configurations.

Exploitability

Exploitation requires an authenticated MCP caller or a prompt injection attack against an MCP agent, making it moderately difficult but possible with existing access to the system.

Blast radius

The vulnerability can lead to full system compromise on deployments using the official Docker image where njs/perl modules are enabled, affecting all services running under Nginx UI's control.

Detection

No reliable host or network indicator is derivable from the published description.

Prioritized remediation

Upgrade to version 2.4.1 or later to fix the configuration validation bypass in the MCP tool's config_add.go component.

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.