DEF CON 19 - Artem Dinaburg - Bit-squatting: DNS Hijacking Without Exploitation

What people said

hayst4ck · 2022-09 · Strong recommendation

A really fun DefCon talk on bitsquatting. Bitsquatting is the practice of registering domains that are one bit off from a popular one: [VIDEO] google.com vs ooogle.com >>> chr(int('0b1100111', 2)) 'g' >>> chr(int('0b1101111', 2)) 'o' If the 4th to last bit of 'g' were to flip before writing to disk, you could get persistent requests to ooogle.com Having done queries against very large datasets at a large company, I can say for certain that this happens much more than you think it might.

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btschaegg · 2018-08 · Recommendation

Regarding "some hardware errors": This might include operationg conditions you didn't consider; say: The divisor in your code went through a non-ECC DRAM module (maybe in a disk drive) that runs hotter than its specified operating temperature would allow and a random bit-flip changes your `1` into a `0`. On this topic, the talk on Bitsquatting from Artem Dinaburg during Defcon 19 is worth watching. The most interesting part on bit flips starts around 15:05 minutes: [VIDEO]

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josephg · 2023-10 · Reference

Encryption and signing don't protect against memory corruption. For example, I download software from the internet then hash it. The hash matches. Before the bytes are written to disk locally, a bit flips in RAM. The corrupted data is written to disk and used. Likewise, dnssec doesn't protect you against DNS bitsquatting attacks[1] because the domain name can be changed before the DNS request is made. So the DNS response your computer makes for a-azon.com might be totally valid and signed. It can come through DoH or whatever. The problem is that your browser thought it was the response for amazon.com and chrome send a bitsquatter your amazon cookies. (Oops). [1] [VIDEO]

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