This sounds like multiple RCE issues in common PGP and S/MIME software, but the details are vague so far. Or it could be a side channel issue. Hmm.https://twitter.com/EFF/status/995906839958061056 …
Nobody uses that stuff for GPG anyway. It sounds to me like a series of vulns in common core implementations (i.e. gnupg and whatever people use for S/MIME) that are exploitable in an email context (and possibly others).