9Router: Unauthenticated Remote Code Execution via unprotected MCP custom plugin routes
43Vexday Risk Score
Patch soon. It has a working public exploit.
ssvc Attendcvss 10epss 4.6%
exploitation probability
4.6%top 9% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Affected products
decolua · 9router