No one can be that incompetent, surely?
I'd love to believe that this is just HMG trying to do a snowjob(*) on Miranda, Rushbridger et al, or that the journo's are working a sophisticated sting against the spooks; but, to be honest, it really does seem that the Graun and its fellow travellers are a bunch of incompetent innocents who aren't fit to be allowed near an abacus, let alone a sensitive computer system.
These documents would probably have been a lot more secure if Rushbridger and his crew had simply communicated with each other, carefully, via PGP/GPG encrypted emails.
It reminds me of that sniffy comment by Gandalf in LOTR about his exaggerated fear of Sauron vs. his overoptimistic faith in the Innkeeper Butterbur...
(*) well, they are anyway, but I simply can't stack up the comments by the Graun, Miranda and others and still assume that they are in any way competent.