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

Throwable.printStackTrace(...) prints a Throwable and its stack trace to System.Err (by default) which is not easily parseable and can expose sensitive information:

try {
  /* ... */
} catch(Exception e) {
  e.printStackTrace(); // Sensitive
}

EnableWebSecurity annotation for SpringFramework with debug to true enables debugging support:

import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;

@Configuration
@EnableWebSecurity(debug = true) // Sensitive
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
  // ...
}

WebView.setWebContentsDebuggingEnabled(true) for Android enables debugging support:

import android.webkit.WebView;

WebView.setWebContentsDebuggingEnabled(true); // Sensitive
WebView.getFactory().getStatics().setWebContentsDebuggingEnabled(true); // Sensitive

Compliant Solution

Loggers should be used (instead of printStackTrace) to print throwables:

try {
  /* ... */
} catch(Exception e) {
  LOGGER.log("context", e);
}

EnableWebSecurity annotation for SpringFramework with debug to false disables debugging support:

import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;

@Configuration
@EnableWebSecurity(debug = false)
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
  // ...
}

WebView.setWebContentsDebuggingEnabled(false) for Android disables debugging support:

import android.webkit.WebView;

WebView.setWebContentsDebuggingEnabled(false);
WebView.getFactory().getStatics().setWebContentsDebuggingEnabled(false);

See