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Waiting for the Worms

Posted 09/20/2001 - 2:47am EDT [Discussion]

I got some good information from two readers on ways to prevent Nimda and its
ilk from propagating. The first is a list of suggestions for securing Outlook,
courtesy of reader Bill Krick:

There is a very simple way to help stop the spread of many email viruses for Outlook Express users (the vast majority) that you should pass along to
your readers.



Here's what to do.



1. Tools -> Options -> Security

Change the Security Zone to "Restricted sites zone". This will prevent it from automatically running imbedded script viruses.



2. Tools -> Options -> Send

Change mail sending format to "Plain text" and uncheck "Reply to messages using the format in which they were sent". This will prevent infected machines from spreading script viruses through
email.



3. Force Windows to display the entire filenames. Open Windows Explorer, click on View -> Folder Options -> View, then UNcheck the "Hide file extensions for known file types" option. This will show you the full extension of all files for the next step.



4. Be wary of all file attachments regardless of who they are from. Don't open attachments with the following extensions under any circumstances:

.EXE .COM .BAT .PIF .LNK. SCR. JS. VBS. DOC.



There are hundreds of other potentially "bad" extensions as well but the above are the most commonly used by viruses.



For more info on "unsafe" extensions, go here.