A quick and dirty fix to such compiler attacks could be to have proper network watchdogs setup, and paying attention to the logs they generate.

For example, init and login should not be accessing the network! Of course one can go one step deeper and inspect all file-handles opened by all the process. As a process can write stuff to a hidden log (and indeed memory!), and then some ok-looking process can fire up and do the actual net transfer. etc

Of course, this would have to be a hardened kernel level module.

So a little extra vigilance can take care of such attacks. But the crypto-weakening attacks don't seems to be so straight forward to manage. imho.

My point is not to compare FOSS with the rest of the closed source stuff. FOSS definitely has an advantage with the "many eyes" effect etc. But that still does not guarantee that the 'control freaks' wont be able to sneak in something sinister into a benign looking app in an major Linux distro. Question is whether the FOSS community would go through some sort of SOP yet again for 'driving out these demons'.