[Evolution] Tell how to handle malicious email in Evolution Help and make defanged examples into a test suite

[Lee McKusick <leemck gmail com>]

I am writing to suggest the Evolution help file be updated with
instructions on how to safely capture a malicious email, and further,
how to deal with some of the malicious emails and yet further, how to
clean up the system if a really persistent bad email can not be
removed.

Additionally, we should have a way of collecting some captured emails,
defanging them and making them available as test tools so a system
administrator can confirm instances of Evolution on user machines are
updated and safe from malicious take-over. 

I got a really nasty email that drew red lines and switched all
incoming mail to the Junk folder. Fooling me for several days.

I have been running Evolution on Ubuntu Linux for years. The other day
about November 8, 2018. I received a remarkably malicious email, which
was so nasty I deleted it with prejudice.

This email drew a red line through about six subject lines 3 above and
3 below itself. Further, this email routed all my incoming mail to the
Junk folder. 

My guess is the method of drawing red lines was accomplished by filling
the subject line with terminal control characters. That is an old trick
dating back to teletype terminals that used backspace and overtyping to
underline text.

I started searching trying to find guidance on how to handle this
email. I was puzzled that I simply couldn't find any good current
information about this malicious email. My guess is this malicious
email is an old trick being deliberately sent in hopes that the odd
Evolution user such as myself is at the other end.

The second trick that the malicious email did, is it routed all my
emails to the Junk folder. This email appears to have poked a false
account name called "Enabled checkbox On this computer Default
greencheckbox maildir" into the preferences->account name table.

Man, how did they do that? 

So it is a pretty nasty email.