Framelink Figma MCP Server before 0.6.3 allows an unauthenticated remote attacker to execute arbitrary operating system commands via a crafted HTTP POST request with shell metacharacters in input that is used by a fetchWithRetry curl command. The vulnerable endpoint fails to properly sanitize user-supplied input, enabling the attacker to inject malicious commands that are executed with the privileges of the MCP process. Exploitation requires network access to the MCP interface.
The product protects a primary channel, but it does not use the same level of protection for an alternate channel.