Yes. It’s even more possible for a teacher to, down the line, be reviewing the grades they’ve assigned and recall you weren’t exactly an A++++ student.
This sort of thing happens all the time (it pops up in my Google alerts) and almost without exception the perpetrator is caught because their teacher was pretty damn sure they didn’t pass the class with flying colors.
The weakest link in the system is when transcripts get sent. They’re sealed from school => university. If you know any former Stasi agents, ask them about steaming and re-sealing mail. And then, if you know any U.S. Postal Inspectors, ask them about penalties for interfering with the mail and its delivery.