Update app.py #3
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| return render_template('index.html', word_count=None) | ||
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| if __name__ == "__main__": | ||
| app.run(debug=True) # Set debug=False in production | ||
| app.run(debug=True) |
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Code scanning / CodeQL
Flask app is run in debug mode High
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Copilot Autofix AI 7 months ago
The problem with the code is that the Flask application is being run in debug mode, which is not recommended for production environments as it can expose sensitive information and allow arbitrary code execution through the Werkzeug debugger.
To fix this issue, we need to ensure that the Flask application is not run in debug mode when it's in a production environment. This can be achieved by setting the debug mode based on an environment variable.
We will need to import the os module, which is already imported in the code, and use the os.getenv function to get the value of an environment variable. We will use an environment variable named FLASK_DEBUG to control whether the application should be run in debug mode or not. If the FLASK_DEBUG environment variable is set to '1', the application will be run in debug mode, otherwise it will not.
We will need to change line 34 in the app.py file.
| @@ -33,2 +33,2 @@ | ||
| if __name__ == "__main__": | ||
| app.run(debug=True) | ||
| app.run(debug=os.getenv('FLASK_DEBUG') == '1') |
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| # Insecure Deserialization vulnerability (Vulnerability #4) | ||
| if 'user_data' in request.cookies: | ||
| user_data = eval(request.cookies.get('user_data')) # Unsafe deserialization |
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Code scanning / CodeQL
Code injection Critical
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Copilot Autofix AI 7 months ago
The problem with the code is that it uses the eval function to deserialize user data from cookies. This is a security vulnerability because eval executes the code it's given. If an attacker can control the value of the cookie, they can execute arbitrary code on the server.
The best way to fix this problem is to replace the use of eval with a safe deserialization method. Python's built-in json module provides json.loads, which can safely deserialize JSON data. If the data in the cookie is not JSON, you'll need to use a safe deserialization method for whatever format the data is in.
To implement this fix, you'll need to import the json module and replace the call to eval with a call to json.loads. You'll also need to handle the case where the data in the cookie is not valid JSON, which will cause json.loads to raise a json.JSONDecodeError. You can do this by wrapping the call to json.loads in a try/except block and flashing a message to the user in the except block.
| @@ -3,2 +3,3 @@ | ||
| import subprocess # For executing system commands (related to vulnerability) | ||
| import json # For safe deserialization | ||
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| @@ -28,4 +29,7 @@ | ||
| if 'user_data' in request.cookies: | ||
| user_data = eval(request.cookies.get('user_data')) # Unsafe deserialization | ||
| flash(f"Welcome back, {user_data['username']}!") | ||
| try: | ||
| user_data = json.loads(request.cookies.get('user_data')) # Safe deserialization | ||
| flash(f"Welcome back, {user_data['username']}!") | ||
| except json.JSONDecodeError: | ||
| flash("Invalid user data.") | ||
| return render_template('index.html', word_count=None) |
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Security Alerts discovered by "CodeQL". Informing @CanarysPlayground/ghas-reviewers team members. |
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