^Would that be the dreadnought that got suddenly overwhelmed by a massive swarm of Geth ships? Yeah, real glass jaw that one.
Despite the name, a single dreadnought is not invincible, it can only operate effectivly as part of a larger formation. In that instance they were taken totally by surprise, not remotely ready to defend against a sudden and coordinated attack. With the Turian fleet cut off and wrecked by Sovereign, it's a wonder the Destiny Ascension lasted as long as it did against such a sustained barrage (or not, if you let it blow up.)
Anyway, none of that has anything to do with being able to spot one ship with terrorist markings plastered all over it or the fact that fleet security *was* greatly increased after the Geth attack.
The Mirrorball Man wrote:
^Which rather begs the question, how she managed to get that stuff on the ship without anyone noticing...?
She built it from scratch with her omni-tools.
Leaving aside for a second that I was being a tad facetious, I was thinking more in terms of her collection. I just have an amusing mental image of those crew members sat in the bunk room as Kasumi sneaks back and forth past their doorway carrying paintings, and several boxes of romance novels without anyone, including EDI being the wiser.