Net Error Handling Strategy
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can be done in three ways in .NET 5 Vulnerable Patterns for Error Handling 5.1 Page_Error 5.2 Global.asax 5.3 Web.config 6 Best Practices for Error Handling 6.1 Try & Catch (Java/ .NET) owasp information leakage and improper error handling 6.2 Releasing resources and good housekeeping 6.3 Centralised exception handling (Struts Example) Error, Exception
Owasp Improper Error Handling
handling & Logging. Contact author: Eoin Keary An important aspect of secure application development is to prevent information leakage. Error messages give
Application Error Message Security Vulnerability
an attacker great insight into the inner workings of an application. The purpose of reviewing the Error Handling code is to assure the application fails safely under all possible error conditions, expected and unexpected. No
Owasp Error Handling Cheat Sheet
sensitive information is presented to the user when an error occurs. For example SQL injection is much tougher to successfully pull off without some healthy error messages. It lessens the attack footprint and our attacker would have to resort to use “blind SQL injection” which is more difficult and time consuming. A well-planned error/exception handling strategy is important for three reasons: Good error handling does not give an attacker any information which poor error handling server error message ( 10932 ) is a means to an end, attacking the application A proper centralised error strategy is easier to maintain and reduces the chance of any uncaught errors “Bubbling up” to the front end of an application. Information leakage can lead to social engineering exploits. Some development languages provide checked exceptions which mean that the compiler shall complain if an exception for a particular API call is not caught Java and C# are good examples of this. Languages like C++ and C do not provide this safety net. Languages with checked exception handling still are prone to information leakage as not all types of error are checked for. When an exception or error is thrown we also need to log this occurrence. Sometimes this is due to bad development, but it can be the result of an attack or some other service your application relies on failing. All code paths that can cause an exception to be thrown should check for success in order for the exception not to be thrown. To avoid a NullPointerException we should check is the object being accessed is not null. Generic error messages We should use a localized description string in every exception, a friendly error reason such as “System Error – Please try again later”. When
We would catch it and write it to a log. More sophisticated versions even featured a stack trace. Yes, really, we were that advanced :) The reason we did that was error message on page simple, VB didn't have structured exception handling and if your application threw an unhandled error it error handling best practices simply crashed. There was no default way of knowing where the exception had taken place. .NET has structured exception handling, but the VB poor error handling: unhandled exception mindset of wrapping every piece of code in a try-catch block, where the catch catches System.Exception, is still common, I see it again and again in enterprise development teams. Usually it includes some logging framework and looks something https://www.owasp.org/index.php/Error_Handling like this: try { // do something } catch (Exception exception) { Logger.LogException("Something bad just happened", exception); } Catching System.Exception is the worst possible exception handling strategy. What happens when the application continues executing? It's probably now in an inconsistent state that will cause extremely hard to debug problems in some unrelated place, or even worse, inconsistent corrupt data that will live on in the database for years to come. If you re-throw from the catch http://mikehadlow.blogspot.com/2009/08/first-rule-of-exception-handling-do-not.html block the exception will get caught again in the calling method and you get a ton of log messages that don't really help you at all. It is much better to simply allow any exceptions to bubble up to the top of the stack and leave a clear message and stack trace in a log and, if possible, some indication that there's been a problem on a UI. In fact there are only three places where you should handle exceptions; at the process boundary, when you are sure you can improve the experience of the person debugging your application, and when your software can recover gracefully from an expected exception. You should always catch exceptions at the process boundary and log them. If the process has a UI, you should also inform the user that there has been an unexpected problem and end the current business process. If you allow the customer to struggle on you will most likely end up with either corrupt data, or a further, much harder to debug, problem further down the line. Improving the debugging experience is another good reason for exception handling. If you know something is likely to go wrong; a configuration error for example, it's worth catching a typed error (never System.Exception) and adding some context. You could explain clearly that a configuration section is missing or incorrect and give
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and http://stackoverflow.com/questions/5192898/exception-handling-and-logging-strategy-in-net policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags https://www.simple-talk.com/dotnet/asp-net/handling-errors-effectively-in-asp-net-mvc/ Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only error handling takes a minute: Sign up Exception handling and logging strategy in .NET up vote 12 down vote favorite 4 I am building a multi-layered application that has an ASP.NET MVC web application. It conists of the usuals like presentation layer, business layer, data layer, etc. How would one create/use a decent exception handling mechanism? I read on Patterns and Practices that improper error handling you need to bubble up exceptions to the various layers. Also logging. Where does logging take place? In the MVC web application? How would you redirect to various error pages depending on the type of error? I would appreciate some feedback regarding this, and some articles if you guys have some. If there are any sample apps that make use of a decent exception hadling and logging strategy please let me know :) c# .net asp.net exception-handling asp.net-mvc-3 share|improve this question edited Mar 4 '11 at 11:11 asked Mar 4 '11 at 11:05 Brendan Vogt 11.2k1799183 add a comment| 5 Answers 5 active oldest votes up vote 7 down vote accepted First, I would suggest reading the article "Vexing Exceptions" by Eric Lippert. This should give you some reasonable guidance on exception-handling (and more on exception throwing). When it comes to exception logging, the easiest and cleanest approach is to have a "top-level" exception handler responsible for dealing with all otherwise unhandled exceptions and record them to a log for analysis. This can be done in ASP.NET applications through the HttpApplication.Error
Effectively in ASP.NET MVC 10 April 2014Handling Errors Effectively in ASP.NET MVCASP.NET MVC gives you more options in the way that you handle exceptions. Error handling isn't intrinsically exciting, but there are many ways of avoiding the classic yellow page of death, even getting ELMAH to manage error handling for you. 80 3 Dino Esposito Years ago, ASP.NET's error handling was one of the major things that made me wonder if ASP.NET MVC could give me something that ASP.NET Web Forms couldn't. Web Forms is based on pages; so if something goes wrong, all that you can do is to redirect the user to another page and explain what the error was or just be generically sorry. ASP.NET Web Forms allow you to map an error page for each possible HTTP status code. You control the mapping through the