Back in 2011 a hacker managed to generate legitimate signed certificates for
gmail.com and other communication domains.
Practically speaking, is that enough for him to eavesdrop on any person's communication? My understanding is that the attacker would at the very least need DNS spoofing to lure victims to "bad"
gmail.com and then need "bad"
gmail.com to mimic actual
gmail.com to fool people into entering passwords/sending mails. If the attacker controls a network (such as wifi at a cafe), he could configure an SSL proxy with this "bad" certificate and get all the communication, but lets assume that isn't the case.
My question is: How can legitimate certificates obtained by bad guys for known domains cause a problem on their own?