Honestly, it would be irresponsible and surprising if Israel _didn't_ try to sabotage Iran's nuclear program, especially given some of the things that the Iranians were saying publicly at the time.
What negative stereotype? That Israel has excellent cyber capacity?
Sure, there wasn't any official attribution, but the US aren't the only player in town either.
EDIT: As an aside, an ex-director of the DGSE[1] (french CIA basically) complained that there tend to be a general misunderstanding between the communication modes of western countries and middle-east countries, the former prefers to proverbially "Speak softly and carry a big stick" while the latter prefer a good incendiary speech as a form of catharsis. As a result western audiences tend to take some speeches too literally, as if they were a plan of action while the discourse wasn't made with them in mind.
It's not like they don't have extremely good cyber capacity, or incentives to hinder an iranian nuclear program.