Can I suggest two possibilities not apparently being considered? (1) These messages may be a sort of generator for phishing targets. (This is not currently a likely scenario, but you want to consider it.)
(2) These might be either the body of a message sent by a spatter steganography technique, or they might be setting up a noise background against which to send steganographically encoded messages. I'd suggest a third, which is true tin-foil-hat stuff, but you who are into conspiracy theories can work that out yourselves. Whenever I see a sudden rise in odd-looking spam, I tend to assume something like the second possibility. https://en.wikipedia.org/wiki/Steganography -- Joel Rees One of these days I'll get someone to pay me to design a language that combines the best of Forth and C. Then I'll be able to leap wide instruction sets with a single #ifdef, run faster than a speeding infinite loop with a #define, and stop all integer size bugs with my bare cast. http://defining-computers.blogspot.com/2017/06/reinventing-computers.html More of my delusions: http://reiisi.blogspot.com/2017/05/do-not-pay-modern-danegeld-ransomware.html http://reiisi.blogspot.jp/p/novels-i-am-writing.html