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AlotOfReadingyesterday at 5:25 PM2 repliesview on HN

Computing a CRC is equivalent to attacking it. The checksum is the value that produces a certain fixed constant when appended to the data. This is why you'll often see checksums as the last field in a message. It allows for hardware to verify the entire message by checking if the CRC of the bytes equals that fixed constant without having to parse it.


Replies

brokenmachinetoday at 12:35 AM

It's trivially easy to create a malicious file with the same CRC as another file.

So "verifying" using CRC is very stupid if you're trying to prevent malicious execution. You need to use cryptographic signatures.