Gemini MCP tool had critical unauthenticated command injection vulnerability

Jan 2026

CVE-2026-0755, a critical command injection vulnerability (CVSS 9.8) in gemini-mcp-tool, allowed unauthenticated remote attackers to execute arbitrary code on systems running the MCP server for Gemini CLI integration. The execAsync method failed to sanitize user-supplied input before constructing shell commands, enabling attackers to inject arbitrary commands via shell metacharacters with no authentication required. No fixed version was available at the time of publication.