Approximately how long does it take to collide a CRC naively? I'm guessing there's a trick that makes it faster, these days?

It takes my computer on a single core about 7 minutes to find a nonce for an arbitrary files sha256 to prefix the left side with 4 or 5 zeros (like bitcoin difficulty doubling). Obviously the heat death of the universe would occur trying to collide sha256 on a single core, but CRC - Gemini says it depends on the algorithm, but crc 32 should take about an hour to collide, but it didn't specify "any" or "arbitrary" collisions, but mentioned "any" right before that. So if the most probable sentence after "any collision" is a time estimate, with the logic of LLM implies that's the easier case of any collision.

I'm surprised brute force is even needed. As far as I know, CRC has absolutely no intent to be a cryptographically secure one-way function. It is purely used against unintentional corruption of data. With that in light, does it really take an hour to find a collision? Can't you construct one much quicker?

Once saw a writeup where someone figured out how to reverse the crc32 calculation… Absolutely no brute forcing needed!

Oddly, this kind of topic doesn’t get a lot of attention