Aiosmtpd — the complete, unedited output of the deterministic mcptrustchecker engine v1.5.0, scanned . Every finding, capability tag and score component below is exactly what the engine produced — no AI, no post-processing.
{
"tool": {
"name": "mcptrustchecker",
"version": "1.5.0",
"methodologyVersion": "mcptrustchecker-1.4"
},
"target": {
"id": "aiosmtpd",
"source": {
"kind": "package",
"origin": "aiosmtpd"
},
"server": {
"name": "aiosmtpd"
}
},
"grade": "B",
"score": {
"score": 85,
"grade": "B",
"band": "B",
"categorySubtotals": {
"injection": 15.4,
"exfiltration": 0,
"permissions": 0,
"supply-chain": 0,
"network": 0,
"hygiene": 0
},
"vector": [
{
"ruleId": "MTC-SRC-004",
"category": "injection",
"severity": "high",
"confidence": "strong",
"rawWeight": 22,
"confidenceMult": 0.7,
"diminishingFactor": 1,
"appliedPenalty": 15.4
}
],
"gatesFired": [],
"methodologyVersion": "mcptrustchecker-1.4"
},
"capability": {
"level": "high",
"reasons": [
"reads sensitive or local data",
"has a read → egress path (a data-exfiltration surface)",
"can execute shell commands or code"
],
"tags": [
"sensitive-source",
"code-exec"
]
},
"coverage": {
"level": "source",
"inputs": {
"toolSurface": false,
"implementationSource": true,
"packageMetadata": true,
"liveTransport": false
},
"caveats": [
"No tools were enumerated, so prompt-injection, capability and toxic-flow analysis had no tool surface to inspect. To grade a package’s real runtime tools, scan the running server: --command \"npx -y <package>\"."
]
},
"findings": [
{
"ruleId": "MTC-SRC-006",
"title": "Reads a sensitive credential path or dumps the environment (housekeep.py)",
"category": "exfiltration",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`housekeep.py:100`): Reading private keys / cloud credentials, or serializing the whole environment, is a sensitive-data source that becomes exfiltration when combined with any egress. 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": "housekeep.py"
},
"evidence": "dict(os.environ)",
"owasp": "LLM02:2025 Sensitive Information Disclosure",
"data": {
"rule": "MTC-SRC-006",
"file": "housekeep.py",
"line": 100
}
},
{
"ruleId": "MTC-SRC-004",
"title": "Obfuscated / encoded payload in server code (aiosmtpd/tests/test_proxyprotocol.py)",
"category": "injection",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`aiosmtpd/tests/test_proxyprotocol.py:339`): Decoding an encoded blob and executing it is how malicious logic is hidden from human review of the source. 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": "aiosmtpd/tests/test_proxyprotocol.py"
},
"evidence": "\\x20\\x00\\x17\\x01\\x02\\x03\\x04\\x05\\x21\\x00\\x07",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-004",
"file": "aiosmtpd/tests/test_proxyprotocol.py",
"line": 339
}
},
{
"ruleId": "MTC-SRC-001",
"title": "Dynamic code execution in server code (aiosmtpd/docs/_exts/autoprogramm.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`aiosmtpd/docs/_exts/autoprogramm.py:184`): 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": "aiosmtpd/docs/_exts/autoprogramm.py"
},
"evidence": "eval(",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-001",
"file": "aiosmtpd/docs/_exts/autoprogramm.py",
"line": 184
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (aiosmtpd/docs/_exts/autoprogramm.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`aiosmtpd/docs/_exts/autoprogramm.py:172`): 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": "aiosmtpd/docs/_exts/autoprogramm.py"
},
"evidence": "exec(",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "aiosmtpd/docs/_exts/autoprogramm.py",
"line": 172
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (aiosmtpd/qa/test_0packaging.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`aiosmtpd/qa/test_0packaging.py:44`): 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": "aiosmtpd/qa/test_0packaging.py"
},
"evidence": "subprocess.check_output(",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "aiosmtpd/qa/test_0packaging.py",
"line": 44
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (release.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`release.py:101`): 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": "release.py"
},
"evidence": "subprocess.run(",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "release.py",
"line": 101
}
},
{
"ruleId": "MTC-SRC-005",
"title": "Dynamic module load from a non-literal (aiosmtpd/docs/_exts/autoprogramm.py)",
"category": "permissions",
"severity": "medium",
"confidence": "heuristic",
"description": "In the server's implementation (`aiosmtpd/docs/_exts/autoprogramm.py:155`): Loading a module chosen at runtime (from a variable) can pull in and run attacker-influenced code paths. 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": "aiosmtpd/docs/_exts/autoprogramm.py"
},
"evidence": "__import__(",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-005",
"file": "aiosmtpd/docs/_exts/autoprogramm.py",
"line": 155
}
}
],
"toxicFlows": [],
"capabilities": [],
"surfaceDigest": "1690c99eaa2ff85c54ddb61028cef06ada4cb6dc2c6515acdbd4329cdfeac110",
"stats": {
"tools": 0,
"prompts": 0,
"resources": 0,
"findingsBySeverity": {
"critical": 0,
"high": 6,
"medium": 1,
"low": 0,
"info": 0
}
}
}