CVE-2026-46339 PUBLISHED

9Router: Unauthenticated Remote Code Execution via unprotected MCP custom plugin routes

Assigner: GitHub_M
Reserved: 13.05.2026 Published: 15.07.2026 Updated: 16.07.2026

9Router is an AI router & token saver. From 0.4.30 until 0.4.37, 9Router's src/proxy.js middleware did not protect /api/cli-tools/ and /api/mcp/, allowing unauthenticated registration of customPlugins through src/app/api/cli-tools/cowork-settings/route.js and command execution through the MCP bridge. This vulnerability is fixed in 0.4.37.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS Score: 10

Attack Vector	Network	Scope	Changed
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	decolua
Product	9router
Versions	Version >= 0.4.30, < 0.4.37 is affected

References

Problem Types

CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') CWE
CWE-306: Missing Authentication for Critical Function CWE