mcp-server-semgrep/semgrep-rules/python/cryptography/security/insufficient-rsa-key-size.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: insufficient-rsa-key-size
  patterns:
  - pattern-either:
    - pattern: cryptography.hazmat.primitives.asymmetric.rsa.generate_private_key(..., key_size=$SIZE,
        ...)
    - pattern: cryptography.hazmat.primitives.asymmetric.rsa.generate_private_key($EXP, $SIZE, ...)
  - metavariable-comparison:
      metavariable: $SIZE
      comparison: $SIZE < 2048
  - focus-metavariable: $SIZE
  fix : |
      2048
  message: >-
    Detected an insufficient key size for RSA. NIST recommends
    a key size of 2048 or higher.
  metadata:
    cwe:
    - 'CWE-326: Inadequate Encryption Strength'
    owasp:
    - A03:2017 - Sensitive Data Exposure
    - A02:2021 - Cryptographic Failures
    source-rule-url: https://github.com/PyCQA/bandit/blob/b1411bfb43795d3ffd268bef17a839dee954c2b1/bandit/plugins/weak_cryptographic_key.py
    references:
    - https://cryptography.io/en/latest/hazmat/primitives/asymmetric/rsa/
    - https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57Pt3r1.pdf
    category: security
    technology:
    - cryptography
    subcategory:
    - audit
    likelihood: MEDIUM
    impact: MEDIUM
    confidence: MEDIUM
    functional-categories:
    - crypto::search::key-length::cryptography
  languages: [python]
  severity: WARNING