40 lines
982 B
Plaintext
40 lines
982 B
Plaintext
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=== How to fix it in Python Standard Library
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include::../../common/fix/code-rationale.adoc[]
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==== Noncompliant code example
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[source,python,diff-id=1,diff-type=noncompliant]
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----
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import logging
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logger = logging.getLogger(__name__)
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@app.route('/example')
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def log():
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data = request.args["data"]
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logger.log(logging.CRITICAL, "%s", data) # Noncompliant
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----
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==== Compliant solution
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[source,python,diff-id=1,diff-type=compliant]
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----
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import logging
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import base64
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logger = logging.getLogger(__name__)
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@app.route('/example')
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def log():
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data = request.args["data"]
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if data.isalnum():
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logger.log(logging.CRITICAL, "%s", data)
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else:
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logger.log(logging.CRITICAL, "Invalid Input: %s", base64.b64encode(data.encode('UTF-8')))
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----
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include::../../common/fix/how-does-this-work.adoc[]
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Here, the example compliant code uses the `isalnum` function to ensure the untrusted data is safe. If not, it performs Base64 encoding to protect from log injection.
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