On Tue, Jun 17, 2014 at 11:51 AM, John C Klensin <john-ietf(_at_)jck(_dot_)com>
wrote:
The things that I think have security (or significant
operational) impacts include tracking beacons embedded in
messages to tell the sender (at least) when or if they were read
(privacy problem), embedded large images or text that is
automagically downloaded when the message is opened or earlier
(potential DoS attack), embedded malware and scripts of multiple
flavors even if not intentionally hostile, and so on.
Yes, there are many traps for the average user on a MUA that tries
very hard to look spiffy. I like mutt ... but an alternative is to use
a GUI MUA that where you can keep its behavior conservative.
Thunderbird is not bad at that.