When an application error occurs, whether due to user input or an internal function, we as conscientious developers want to present an error message that will help the end user correct the problem. However, it is possible to be too helpful with your error handling approach. By providing overly detailed application error messages to your users, you can actually be opening your site to hackers. Hackers spend the majority of their time performing reconnaissance on a site, slowly gathering multiple pieces of information to determine how a site is vulnerable. Sometimes, it is a seemingly innocuous piece of information in an application error message that provides an attacker with the last piece of the puzzle necessary for him to launch a devastating attack.
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