Build123d — the complete, unedited output of the deterministic mcptrustchecker engine v1.13.0, scanned . Every finding, capability tag and score component below is exactly what the engine produced — no AI, no post-processing.
{
"tool": {
"name": "mcptrustchecker",
"version": "1.13.0",
"methodologyVersion": "mcptrustchecker-1.13"
},
"target": {
"id": "build123d-mcp",
"source": {
"kind": "package",
"origin": "build123d-mcp"
},
"server": {
"name": "build123d-mcp"
}
},
"grade": "B",
"score": {
"score": 87,
"threatScore": 94,
"grade": "B",
"band": "B",
"categorySubtotals": {
"injection": 0,
"exfiltration": 0,
"permissions": 6.3,
"supply-chain": 0,
"network": 0,
"hygiene": 0
},
"vector": [
{
"kind": "threat",
"ruleId": "MTC-SRC-007",
"category": "permissions",
"severity": "medium",
"confidence": "strong",
"rawWeight": 9,
"confidenceMult": 0.7,
"diminishingFactor": 1,
"appliedPenalty": 6.3
},
{
"kind": "client",
"term": "capability-exposure",
"level": "high",
"label": "capability blast radius (high) — client exposure if the model is manipulated",
"appliedPenalty": 6
},
{
"kind": "client",
"term": "verification-discount",
"level": "repo",
"label": "publisher verification (public source) — no provenance, but the source is public and inspectable",
"appliedPenalty": 1
},
{
"kind": "client",
"term": "coverage-honesty",
"level": "source",
"label": "inspection depth (source) — how much of the target the scan could see",
"appliedPenalty": 0
}
],
"gatesFired": [],
"methodologyVersion": "mcptrustchecker-1.13"
},
"capability": {
"level": "high",
"reasons": [
"can send data / act on an external service",
"can execute shell commands or code"
],
"tags": [
"external-sink",
"code-exec"
]
},
"coverage": {
"level": "source",
"inputs": {
"toolSurface": true,
"implementationSource": true,
"packageMetadata": true,
"liveTransport": false
},
"caveats": [
"Tools were statically extracted from the published source (38 recovered), not enumerated from a running server. Tool-poisoning, Unicode-smuggling, capability and toxic-flow analysis ran on this inferred surface, but a mis-parsed registration could be missed or mis-attributed, so tool-derived findings are capped below “confirmed”. To grade the real runtime surface, scan the running server: --command \"npx -y <package>\"."
]
},
"findings": [
{
"ruleId": "MTC-SRC-001",
"title": "Dynamic code execution in server code (src/build123d_mcp/tools/library.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/tools/library.py:160`): Evaluating strings as code is the most direct RCE primitive; if any tool input reaches it, the server executes attacker-chosen code. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/tools/library.py"
},
"evidence": "tricted_builtins()} exec(compile(source, entry[\"path\"], \"exec\"), namespace) # noqa: S102 if \"make\" not in name",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-001",
"file": "src/build123d_mcp/tools/library.py",
"line": 160,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-001",
"title": "Dynamic code execution in server code (src/build123d_mcp/tools/resolve.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/tools/resolve.py:234`): Evaluating strings as code is the most direct RCE primitive; if any tool input reaches it, the server executes attacker-chosen code. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/tools/resolve.py"
},
"evidence": "try: result = eval(expression, namespace) # noqa: S307 except Exception as exc: return json.dumps",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-001",
"file": "src/build123d_mcp/tools/resolve.py",
"line": 234,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/_design_audit_subprocess.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/_design_audit_subprocess.py:13`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/_design_audit_subprocess.py"
},
"evidence": "parent bound it with ``subprocess.run(timeout=)`` and kill this disposable child on overrun, without ever SIGKILLing th",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/_design_audit_subprocess.py",
"line": 13,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/_shape_compare_subprocess.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/_shape_compare_subprocess.py:7`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/_shape_compare_subprocess.py"
},
"evidence": "nds this process with ``subprocess.run(timeout=...)`` so the worker session survives a large or pathological part. Nois",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/_shape_compare_subprocess.py",
"line": 7,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/_shape_op_subprocess.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/_shape_op_subprocess.py:10`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/_shape_op_subprocess.py"
},
"evidence": "parent bounds it with ``subprocess.run(timeout=...)`` so an un-interruptible native call is killed cleanly instead of SI",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/_shape_op_subprocess.py",
"line": 10,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/_tessellate_subprocess.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/_tessellate_subprocess.py:12`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/_tessellate_subprocess.py"
},
"evidence": "ent can hard-kill via ``subprocess.run(timeout=...)``. Mirrors the export mesh gate (``_gate_subprocess``). \"\"\" import",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/_tessellate_subprocess.py",
"line": 12,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/_vtk_render_subprocess_worker.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/_vtk_render_subprocess_worker.py:11`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/_vtk_render_subprocess_worker.py"
},
"evidence": "ent can hard-kill via ``subprocess.run(timeout=...)``. Mirrors ``_tessellate_subprocess`` (#357/#308). \"\"\" import pickl",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/_vtk_render_subprocess_worker.py",
"line": 11,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/security.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/security.py:4`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/security.py"
},
"evidence": "o layers applied before exec() is called: 1. AST inspection — rejects dangerous imports and calls. 2. Restricted bu",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/security.py",
"line": 4,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/session.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/session.py:806`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/session.py"
},
"evidence": "r(buf): exec(compiled, self.namespace) # noqa: S102 # Cancel alarm immediately so it cannot",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/session.py",
"line": 806,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/tools/_bounded.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/tools/_bounded.py:115`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/tools/_bounded.py"
},
"evidence": "try: proc = subprocess.run( [ sys.executable, \"-m\",",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/tools/_bounded.py",
"line": 115,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/tools/design_audit.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/tools/design_audit.py:137`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/tools/design_audit.py"
},
"evidence": "try: proc = subprocess.run( [sys.executable, \"-m\", \"build123d_mcp._design_audit_subprocess\",",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/tools/design_audit.py",
"line": 137,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (src/build123d_mcp/tools/library.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/tools/library.py:160`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/tools/library.py"
},
"evidence": "tricted_builtins()} exec(compile(source, entry[\"path\"], \"exec\"), namespace) # noqa: S102 if \"make\" not in name",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "src/build123d_mcp/tools/library.py",
"line": 160,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-007",
"title": "Unsafe deserialization (src/build123d_mcp/_vtk_render_subprocess_worker.py)",
"category": "permissions",
"severity": "medium",
"confidence": "strong",
"description": "In the server's implementation (`src/build123d_mcp/_vtk_render_subprocess_worker.py:22`): Deserializing untrusted data with these APIs can execute arbitrary code (a well-known RCE gadget class). This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "src/build123d_mcp/_vtk_render_subprocess_worker.py"
},
"evidence": "\") as f: args = pickle.load(f) png = _vtk_render_tesselated( args[\"shape_data\"], args[\"dire",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-007",
"file": "src/build123d_mcp/_vtk_render_subprocess_worker.py",
"line": 22,
"nonRuntime": false
}
}
],
"toxicFlows": [],
"capabilities": [
{
"tool": "execute",
"tags": [],
"reasons": {}
},
{
"tool": "execute_file",
"tags": [],
"reasons": {}
},
{
"tool": "render_view",
"tags": [],
"reasons": {}
},
{
"tool": "measure",
"tags": [],
"reasons": {}
},
{
"tool": "validate",
"tags": [],
"reasons": {}
},
{
"tool": "locate_gate_defects",
"tags": [],
"reasons": {}
},
{
"tool": "design_audit",
"tags": [],
"reasons": {}
},
{
"tool": "analyze_printability",
"tags": [],
"reasons": {}
},
{
"tool": "cross_sections",
"tags": [],
"reasons": {}
},
{
"tool": "inspect_part",
"tags": [],
"reasons": {}
},
{
"tool": "export",
"tags": [
"external-sink"
],
"reasons": {
"external-sink": [
"keyword \"export_to\""
]
}
},
{
"tool": "prepare_drawing",
"tags": [],
"reasons": {}
},
{
"tool": "crop_drawing",
"tags": [],
"reasons": {}
},
{
"tool": "search_library",
"tags": [],
"reasons": {}
},
{
"tool": "load_part",
"tags": [],
"reasons": {}
},
{
"tool": "save_snapshot",
"tags": [],
"reasons": {}
},
{
"tool": "restore_snapshot",
"tags": [],
"reasons": {}
},
{
"tool": "session_state",
"tags": [],
"reasons": {}
},
{
"tool": "health_check",
"tags": [],
"reasons": {}
},
{
"tool": "reset",
"tags": [],
"reasons": {}
},
{
"tool": "destroy_session",
"tags": [],
"reasons": {}
},
{
"tool": "list_sessions",
"tags": [],
"reasons": {}
},
{
"tool": "compare",
"tags": [],
"reasons": {}
},
{
"tool": "find_holes",
"tags": [],
"reasons": {}
},
{
"tool": "find_hole_patterns",
"tags": [],
"reasons": {}
},
{
"tool": "find_bosses",
"tags": [],
"reasons": {}
},
{
"tool": "find_bored_bosses",
"tags": [],
"reasons": {}
},
{
"tool": "find_countersinks",
"tags": [],
"reasons": {}
},
{
"tool": "recognise_features",
"tags": [],
"reasons": {}
},
{
"tool": "resolve",
"tags": [],
"reasons": {}
},
{
"tool": "script",
"tags": [],
"reasons": {}
},
{
"tool": "import_cad_file",
"tags": [],
"reasons": {}
},
{
"tool": "repair_hints",
"tags": [],
"reasons": {}
},
{
"tool": "repair_advice",
"tags": [],
"reasons": {}
},
{
"tool": "last_error",
"tags": [],
"reasons": {}
},
{
"tool": "version",
"tags": [],
"reasons": {}
},
{
"tool": "workflow_hints",
"tags": [],
"reasons": {}
},
{
"tool": "install_skill",
"tags": [],
"reasons": {}
}
],
"surfaceDigest": "9db3be360734f126c4fd75d867c5b201f456c6bca06d4a5cc97aa941ff501cf0",
"stats": {
"tools": 38,
"prompts": 0,
"resources": 0,
"findingsBySeverity": {
"critical": 0,
"high": 12,
"medium": 1,
"low": 0,
"info": 0
}
}
}