Development tools and frameworks usually have options to make debugging easier for developers. Although these features are useful during development, they should never be enabled for applications deployed in production. Debug instructions or error messages can leak detailed information about the system, like the application’s path or file names.

Ask Yourself Whether

There is a risk if you answered yes to any of those questions.

Recommended Secure Coding Practices

Do not enable debugging features on production servers or applications distributed to end users.

Sensitive Code Example

Django application startup:

from django.conf import settings

settings.configure(DEBUG=True)  # Sensitive when set to True
settings.configure(DEBUG_PROPAGATE_EXCEPTIONS=True)  # Sensitive when set to True

def custom_config(config):
    settings.configure(default_settings=config, DEBUG=True)  # Sensitive

Inside settings.py or global_settings.py, which are the default configuration files for a Django application:

DEBUG = True  # Sensitive
DEBUG_PROPAGATE_EXCEPTIONS = True  # Sensitive

Flask application startup:

from flask import Flask

app = Flask()
app.debug = True  # Sensitive
app.run(debug=True)  # Sensitive

The following code defines a GraphQL endpoint with GraphiQL enabled. While this might be a useful configuration during development, it should never be enabled for applications deployed in production:

from flask import Flask
from graphql_server.flask import GraphQLView

app = Flask(__name__)

app.add_url_rule(
    '/graphql',
    view_func=GraphQLView.as_view(
        'graphql',
        schema=schema,
        graphiql=True # Sensitive
    )
)

Compliant Solution

from django.conf import settings

settings.configure(DEBUG=False)
settings.configure(DEBUG_PROPAGATE_EXCEPTIONS=False)

def custom_config(config):
    settings.configure(default_settings=config, DEBUG=False)

DEBUG = False
DEBUG_PROPAGATE_EXCEPTIONS = False

from flask import Flask

app = Flask()
app.debug = False
app.run(debug=False)

from flask import Flask
from graphql_server.flask import GraphQLView

app = Flask(__name__)

app.add_url_rule(
    '/graphql',
    view_func=GraphQLView.as_view(
        'graphql',
        schema=schema
    )
)

See