CVE-2026-84317

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/0xJacky/nginx-ui/commit/23d1934099b05b2a01589b48129dc3d3159d91c2
https://github.com/0xJacky/nginx-ui/releases/tag/v2.4.1
https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-76pm-mq2q-9gcr
https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-76pm-mq2q-9gcr

Configurations

No configuration.

History

13 Oct 2026, 18:17

Type	Values Removed	Values Added
References	~~() https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-76pm-mq2q-9gcr -~~	() https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-76pm-mq2q-9gcr -

12 Oct 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-12 21:17

Updated : 2026-10-13 18:17

NVD link : CVE-2026-84317

Mitre link : CVE-2026-84317

CVE.ORG link : CVE-2026-84317

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-693

Protection Mechanism Failure

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