Vulnerability Advisory : ArcadeDB before 26.7.3 Authentication Bypass via MCP Transport with HIGH Attack Complexity

ArcadeDB versions before 26.7.3 fail to bind the authenticated principal in the MCP HTTP transport, causing all engine permission checks to silently pass as no-ops. Non-root MCP-allowed users can perform arbitrary database writes, DDL, schema mutations, and execute arbitrary JavaScript code via the query tool.