## Why is this an issue?

Catching `System.Exception` seems like an efficient way to handle multiple possible exceptions. Unfortunately, it traps all exception types, including the ones that were not intended to be caught. To prevent any misunderstandings, exception filters should be used. Alternatively, each exception type should be in a separate `catch` block.

### Noncompliant code example

    try
    {
      // do something that might throw a FileNotFoundException or IOException
    }
    catch (Exception e) // Noncompliant
    {
      // log exception ...
    }

### Compliant solution

    try
    {
      // do something
    }
    catch (Exception e) when (e is FileNotFoundException or IOException)
    {
      // do something
    }

### Exceptions

The final option is to catch `System.Exception` and `throw` it in the last statement in the `catch` block. This is the least-preferred option, as it is an old-style code, which also suffers from performance penalties compared to exception filters.

    try
    {
      // do something
    }
    catch (Exception e)
    {
      if (e is FileNotFoundException or IOException)
      {
        // do something
      }
      else
      {
        throw;
      }
    }

## Resources

- CWE - CWE-396 - Declaration of Catch for Generic Exception