Seems to be a set of MUA bugs that are being overblown and hyped up. TL;DR = Don't use HTML email with some mail clients when sending pgp encrypted mail. https://lists.gnupg.org/pipermail/gnupg-users/2018-May/060315.html --srs On 14/05/18, 1:15 PM, "NANOG on behalf of George William Herbert" <nanog-bounces@nanog.org on behalf of george.herbert@gmail.com> wrote: This is likely bad enough operators need to pay attention. @seecurity tweeted: "We'll publish critical vulnerabilities in PGP/GPG and S/MIME email encryption on 2018-05-15 07:00 UTC. They might reveal the plaintext of encrypted emails, including encrypted emails sent in the past. #efail 1/4" Thread starts here: https://twitter.com/seecurity/status/995906576170053633?s=21 I have no particular insight into what it is other than presuming from thread that decryption can be tricked to do bad things. They recommend temporary disabling downthread: "There are currently no reliable fixes for the vulnerability. If you use PGP/GPG or S/MIME for very sensitive communication, you should disable it in your email client for now. Also read @EFF’s blog post on this issue: eff.org/deeplinks/2018… #efail 2/4" -george Sent from my iPhone