Is there ambiguity in "by each" in this context?

The sentence:

"Find all malls that have been visited by each student attending Wolf
Secondary School"

I’ve recently encountered a question like this on a Computer Science test and interpretted it as so:

Return a list of malls, where each mall was visited by at least 1 student attending Wolf Secondary School.

But the "correct" way to answer the question was:

Return a list of malls, where each mall must has been visited by every single
student attending Wolf Secondary School.

I’m curious to if there’s any ambiguity to the original question and if my interpretation was reasonable/justifiable.