Request without certificate validation¶
ID: py/request-without-cert-validation
Kind: problem
Security severity: 7.5
Severity: error
Precision: medium
Tags:
- security
- external/cwe/cwe-295
Query suites:
- python-security-extended.qls
- python-security-and-quality.qls
Click to see the query in the CodeQL repository
Encryption is key to the security of most, if not all, online communication. Using Transport Layer Security (TLS) can ensure that communication cannot be interrupted by an interloper. For this reason, it is unwise to disable the verification that TLS provides. Functions in the requests
module provide verification by default, and it is only when explicitly turned off using verify=False
that no verification occurs.
Recommendation¶
Never use verify=False
when making a request.
Example¶
The example shows two unsafe calls to semmle.com, followed by various safe alternatives.
import requests
#Unsafe requests
requests.get('https://semmle.com', verify=False) # UNSAFE
requests.get('https://semmle.com', verify=0) # UNSAFE
#Various safe options
requests.get('https://semmle.com', verify=True) # Explicitly safe
requests.get('https://semmle.com', verify="/path/to/cert/")
requests.get('https://semmle.com') # The default is to verify.
#Wrapper to ensure safety
def make_safe_request(url, verify_cert):
if not verify_cert:
raise Exception("Trying to make unsafe request")
return requests.get(url, verify_cert)
References¶
Python requests documentation: SSL Cert Verification.
Common Weakness Enumeration: CWE-295.