mcp-builder

Fail

Audited by Gen Agent Trust Hub on Feb 16, 2026

Risk Level: HIGHPROMPT_INJECTIONREMOTE_CODE_EXECUTIONCOMMAND_EXECUTIONEXTERNAL_DOWNLOADS
Full Analysis
  • Indirect Prompt Injection (HIGH): The skill's core workflow relies on ingesting untrusted data from external sources to drive subsequent code generation and execution phases.
  • Ingestion points: The agent is instructed to fetch documentation from modelcontextprotocol.io, GitHub, and arbitrary third-party service API documentation (Phase 1.2, 1.3, and 1.4).
  • Capability inventory: The agent performs code generation (Phase 2) and subsequently executes build/test commands including npm run build, python -m py_compile, and npx @modelcontextprotocol/inspector (Phase 3.2).
  • Sanitization: No sanitization or boundary markers are defined for the external content before it is used to influence agent decisions.
  • Risk: An attacker-controlled documentation page or API specification could inject instructions that cause the agent to generate backdoored code or execute malicious shell commands during the 'Phase 3' testing process.
  • Remote Code Execution (HIGH): The skill directs the user/agent to execute code directly from a remote source via npx from an organization not listed as a trusted source.
  • Evidence: Phase 3.2 instructs the execution of npx @modelcontextprotocol/inspector.
  • Risk: If the npm package is compromised or if the organization name is typo-squatted, it leads to immediate code execution on the host.
  • External Downloads (MEDIUM): The skill fetches several remote files from GitHub and other domains that are not part of the defined trusted organizations list.
  • Evidence: URLs pointing to raw.githubusercontent.com/modelcontextprotocol/... and modelcontextprotocol.io.
  • Command Execution (LOW): The skill requires the ability to execute shell commands to compile and verify code.
  • Evidence: Usage of npm run build and python -m py_compile.
Recommendations
  • AI detected serious security threats
Audit Metadata
Risk Level
HIGH
Analyzed
Feb 16, 2026, 12:44 PM