# Python Security
# Detects weak cryptographic hash primitives.
id: python-weak-hash
name: Weak Hash Primitive
severity: error
category: security
defect_class: injection
inline_tier: blocking
language: python

message: "Weak hash primitive detected (MD5/SHA1) — use SHA-256+ for security-sensitive contexts"

description: |
  MD5 and SHA1 are collision-prone and not suitable for security-sensitive hashing.

  ✅ FIX: prefer hashlib.sha256/sha512 (or stronger, context-appropriate algorithms).

query: |
  (call
    function: (attribute
      object: (identifier) @MOD
      attribute: (identifier) @FN)
    arguments: (argument_list) @ARGS
    (#eq? @MOD "hashlib")
    (#match? @FN "^(md5|sha1)$"))

metavars:
  - MOD
  - FN
  - ARGS

cwe:
  - CWE-327
owasp:
  - A02
confidence: high

has_fix: false

tags:
  - python
  - security
  - crypto
  - weak-hash

examples:
  bad: |
    digest = hashlib.md5(data).hexdigest()

  good: |
    digest = hashlib.sha256(data).hexdigest()