The article says they got 25,000 doses through a "quiet purchase" and made "diplomatic efforts behind the scenes." There is no way in hell they stole 25,000 doses out of China and went on the news to brag about it. They could not even pretend to do it because it sounds retarded. The title is misleading.
Well, considering China is doing clinical trials with their vaccines all over the world, Mossad would not need to get it from mainland China. If they did steal it, they would have targeted one (or many) of the countries where clinical trials are happening rather than trying to infiltrate the lab in mainland China making it.
But in all honesty, it’s likely they just bought from China and are saying they stole it to not trigger Trump, with China playing along.
It would not make much sense for them to so blatantly admit to stealing it if they did steal it, as doing so would seriously damage their good relations with China for no good reason.
They are just announcing the theft publicly to create a pretext/excuse under which they can general issue the Chinese vaccine once it passes clinical trials. If/when the Americans come demanding answers, they can just say they reverse engineered it from the stolen samples while buying it direct from China actually.