MCP Gateway allows easy and secure running and deployment of MCP servers. In versions 0.27.0 and earlier, when MCP Gateway runs in sse or streaming transport mode, it is vulnerable to DNS rebinding. An attacker who can get a victim to visit a malicious website or be served a malicious advertisement can perform browser-based exploitation of MCP servers executing behind the gateway, including manipulating tools or other features exposed by those MCP servers. MCP Gateway is not affected when running in the default stdio mode, which does not listen on network ports. Version 0.28.0 fixes this issue.
The product provides an Applications Programming Interface (API) or similar interface for interaction with external actors, but the interface includes a dangerous method or function that is not properly restricted.
This weakness can lead to a wide variety of resultant weaknesses, depending on the behavior of the exposed method. It can apply to any number of technologies and approaches, such as ActiveX controls, Java functions, IOCTLs, and so on. The exposure can occur in a few different ways:
Identify all exposed functionality. Explicitly list all functionality that must be exposed to some user or set of users. Identify which functionality may be:
Ensure that the implemented code follows these expectations. This includes setting the appropriate access modifiers where applicable (public, private, protected, etc.) or not marking ActiveX controls safe-for-scripting.