# Starter banlist for Python — copy into .aiwg/security/banned-apis.yaml and customize.
# Targets the most common code-execution and deserialization footguns.
version: 1
languages:
  python:
    - pattern: 're:\beval\s*\('
      reason: "Arbitrary code execution if input is attacker-influenced — no sandboxing"
      replacement: "ast.literal_eval for literals; dedicated parser otherwise"
      cwe: "CWE-95"
    - pattern: 're:\bexec\s*\('
      reason: "Arbitrary code execution — even with restricted globals, defeated by tricks"
      replacement: "Explicit dispatch table or sandboxed runtime (RestrictedPython, etc.)"
      cwe: "CWE-95"
    - pattern: 're:pickle\.loads?\b'
      reason: "Arbitrary code execution on untrusted input via __reduce__"
      replacement: "json (untrusted) or signed pickle with HMAC integrity check"
      cwe: "CWE-502"
    - pattern: 're:cPickle\.loads?\b'
      reason: "Same RCE class as pickle.loads"
      replacement: "json or signed serialization"
      cwe: "CWE-502"
    - pattern: 're:marshal\.loads?\b'
      reason: "Untrusted-input RCE via bytecode interpretation"
      replacement: "json or msgpack"
      cwe: "CWE-502"
    - pattern: 're:yaml\.load\s*\((?![^)]*Loader=yaml\.(Safe|CSafe)Loader)'
      reason: "yaml.load without SafeLoader executes arbitrary Python via tags"
      replacement: "yaml.safe_load or yaml.load(..., Loader=yaml.SafeLoader)"
      cwe: "CWE-502"
    - pattern: 're:subprocess\.(?:call|run|Popen|check_output|check_call)\s*\([^)]*shell=True'
      reason: "Shell injection when args are concatenated from user input"
      replacement: "shell=False with argv list (the default); pre-validate any shell strings"
      cwe: "CWE-78"
    - pattern: 're:os\.system\s*\('
      reason: "Shell injection by construction — no argv form"
      replacement: "subprocess.run([...], shell=False, check=True)"
      cwe: "CWE-78"
    - pattern: 're:os\.popen\s*\('
      reason: "Shell-string execution; deprecated"
      replacement: "subprocess.run with argv list"
      cwe: "CWE-78"
    - pattern: 're:input\s*\('
      reason: "In Python 2 only — eval'd input. In Python 3 it's fine; flagged for projects still on 2."
      replacement: "raw_input (Py2) — or drop Py2 support"
      cwe: "CWE-95"
      languages: [python2]
    - pattern: 're:tempfile\.mktemp\b'
      reason: "Race condition between filename creation and open — TOCTOU"
      replacement: "tempfile.mkstemp or NamedTemporaryFile"
      cwe: "CWE-377"
    - pattern: 're:hashlib\.(md5|sha1)\s*\('
      reason: "Cryptographically broken; acceptable only for non-security checksums"
      replacement: "hashlib.sha256+; for non-security use document the rationale"
      cwe: "CWE-327"
      severity: MEDIUM
exclusions:
  paths:
    - "test/**"
    - "tests/**"
    - "**/test_*.py"
    - "**/*_test.py"
    - "conftest.py"
    - "venv/**"
    - ".venv/**"