An attacker could certainly do that, but they could also advertise bogus records (e.g. the MX record in mit.edu's case) with long TTLs so I don't think DNSSEC makes the worst-case recovery time any longer.
The ostensible difference is that they can advertise records that cryptographically lock out corrections, right? (I think this particular critique is mooted by the maximum TTLs mainstream caches will work on). This was Colm Maccarthaigh's scenario on Twitter last week.
I did see Colm's Tweet last week. I'm just not sure what the attacker gains from the lockout being cryptographic, as opposed to being based on old-fashioned DNS caching. If the attacker gets an A record pointing to a bogus IP address cached in a bunch of places, that's just as bad as getting a bogus DNSSEC key cached - either way, users are locked out until the malicious records expire at their resolvers.
DNSSEC makes many things worse, but I don't think this is one.
Yeah, I feel like Paul Wouters also shot this scenario down pretty conclusively, but I'm sort of doing my best to reconstruct what colmmac was talking about and might not be doing the best job of it.
Aha, I think I saw that tweet too and that's where this idea got into my head. I don't know much about the low-level details of DNSSEC so please just ignore that part :)
