@zereight/mcp-gitlab is a Model Context Protocol server for GitLab. Prior to version 2.1.27, the SSE transport mode (SSE=true) exposes all MCP tools without any authentication. The uploadmarkdown tool reads arbitrary files from the server's local filesystem via an unsanitized filepath parameter and uploads them to a GitLab project. Combined, any unauthenticated network-reachable attacker can read /proc/self/environ to steal the server's GITLABPERSONALACCESSTOKEN and achieve full GitLab account takeover. This is the default configuration for Docker deployments. Version 2.1.27 contains a patch.