python.pycryptodome.security.insecure-hash-algorithm.insecure-hash-algorithm-sha1

Verifed by r2c
Community Favorite
profile photo of returntocorpreturntocorp
Author
99,223
Download Count*
LGPL Commons Clause
License

Detected SHA1 hash algorithm which is considered insecure. SHA1 is not collision resistant and is therefore not suitable as a cryptographic signature. Use SHA256 or SHA3 instead.

Run Locally

Run in CI

Semgrep CI docs

Defintion

Edit RuleView Source
Open in Playground 
rules:
  - id: insecure-hash-algorithm-sha1
    message: Detected SHA1 hash algorithm which is considered insecure. SHA1 is not
      collision resistant and is therefore not suitable as a cryptographic
      signature. Use SHA256 or SHA3 instead.
    metadata:
      source-rule-url: https://github.com/PyCQA/bandit/blob/d5f8fa0d89d7b11442fc6ec80ca42953974354c8/bandit/blacklists/calls.py#L59
      cwe:
        - "CWE-327: Use of a Broken or Risky Cryptographic Algorithm"
      owasp:
        - A03:2017 - Sensitive Data Exposure
        - A02:2021 - Cryptographic Failures
      references:
        - https://www.schneier.com/blog/archives/2012/10/when_will_we_se.html
        - https://www.trendmicro.com/vinfo/us/security/news/vulnerabilities-and-exploits/sha-1-collision-signals-the-end-of-the-algorithm-s-viability
        - http://2012.sharcs.org/slides/stevens.pdf
        - https://pycryptodome.readthedocs.io/en/latest/src/hash/sha3_256.html
      category: security
      technology:
        - pycryptodome
      subcategory:
        - vuln
      likelihood: LOW
      impact: MEDIUM
      confidence: MEDIUM
      license: Commons Clause License Condition v1.0[LGPL-2.1-only]
    severity: WARNING
    languages:
      - python
    pattern-either:
      - pattern: Crypto.Hash.SHA.new(...)
      - pattern: Cryptodome.Hash.SHA.new (...)

Examples

insecure-hash-algorithm.py

# cf. https://github.com/PyCQA/bandit/blob/b78c938c0bd03d201932570f5e054261e10c5750/examples/crypto-md5.py

from cryptography.hazmat.primitives import hashes
from Crypto.Hash import MD2 as pycrypto_md2
from Crypto.Hash import MD4 as pycrypto_md4
from Crypto.Hash import MD5 as pycrypto_md5
from Crypto.Hash import SHA as pycrypto_sha
from Cryptodome.Hash import MD2 as pycryptodomex_md2
from Cryptodome.Hash import MD4 as pycryptodomex_md4
from Cryptodome.Hash import MD5 as pycryptodomex_md5
from Cryptodome.Hash import SHA as pycryptodomex_sha
from Crypto.Hash import SHA3_256

# ok:insecure-hash-algorithm-sha1
h_obj = SHA3_256.new()
h_obj.update(b'Some data')
print(h_obj.hexdigest())


# ruleid:insecure-hash-algorithm-sha1
pycrypto_sha.new()

# ruleid:insecure-hash-algorithm-sha1
pycryptodomex_sha.new()