Its an interview question. If you draw a blank on that, rephrase the question for yourself to something like this: "When you think of bugs you've recently fixed in your code, what comes to mind? Which bug had the most interesting story?". If that feels illegal to you, you can check with your interviewer: "I can't remember many weird old bugs, but can I tell you about a bug I fixed the other week?".
Interviews aren't like tests in school. The point isn't to demonstrate knowledge. The point is to demonstrate to the interviewer that you're someone they'd want to work with. What are they looking for? They want someone they can trust technically, and someone they would enjoy working alongside.
This question is great because its an opportunity to demonstrate both of those skills, by asking you to tell a story (social skills) about an experience you had programming. Use it!
Can you think of any bug from that last five months that you could talk about for five minutes in a way that makes you look smart for solving it? That's all you need to do here.
No, my mind goes completely blank. There's nothing wrong with my memory - I can tell you how I patched the timed Grand Theft Auto 1 demo over 25 years ago with SoftICE as a kid, but I assume my brain finds no value in tracking bugs.
You don’t even need a bug where you look smart for solving it. Eg, as an interviewer I also love stories that go like this:
“There was this memory leak in some C++ code that took us weeks to track down that I’m still kicking myself for not finding earlier. It was totally my fault. Let me tell you what happened … … So the moral of the story is -fsanitize=address is smarter than me. But wow did I learn a lot about my tools from that.”
Interviews aren't like tests in school. The point isn't to demonstrate knowledge. The point is to demonstrate to the interviewer that you're someone they'd want to work with. What are they looking for? They want someone they can trust technically, and someone they would enjoy working alongside.
This question is great because its an opportunity to demonstrate both of those skills, by asking you to tell a story (social skills) about an experience you had programming. Use it!