They are not marked as classified. That is something different than not being classified. Any US person with any sort of national security-related job, or any hopes of ever getting one, should think twice.
It's like having a stealth fighter crash in your back yard (this has happened). The pieces are not marked as being classified, but selling them on ebay isn't going to win you friends.
But overall I don't think this would affect you having a security clearance in the future, this isn't the first time leaks happened and I somehow doubt that it would affect security screening.
You are asked a question along the lines of "have you been ever exposed to classified information without having an explicit permission" if you say yes it was on cover of the goddamn washington post they can't do much.
Saying that it was leaked all of the internet, reported by 100's of news sources, fully analysed and you've looked at it yourself to see if you can learn anything from it isn't going to hurt you either.
But overall this isn't like a stealth fighter crashed in your backyard, it's like a stealth fighter crashed in China, they reverse engineered it, mass produced it, it was reviewed by everyone on the planet and you got one to try it out.
>reported by 100's of news sources
That really doesn't matter for many people. Anyone with any links whatsoever to the US military (a large chunk of the US population, including retirees) is bound by orders not to read classified material despite it being all over the newspapers/CNN. This was and still is a big deal re the Snowden material.
So I don't even see how they can be considered "classified" if the US doesn't officially admit they produced them. As far as I understand, there's nothing that carries their signs or any other such marks (like "top secret US government property").
For the reference, the production of Stuxnet by the US was never officially admitted. So you still don't have to answer you've seen something declared as secret by the US if you've seen a report about Stuxnet. And I honestly don't expect the US will soon admit the production of it officially. Unofficially, sure, there's that NYT article reporting what some "American officials" said.
[1] https://en.wikipedia.org/wiki/Pentagon_Papers#The_Supreme_Co...