4 ms·
I wonder if some port knocking schemes can be attacked using a De Bruijn sequence. If the firewall only examines the last N potential knocks amongst K ports, se
by oakwhiz 13y ago
I wonder if some port knocking schemes can be attacked using a De Bruijn sequence. If the firewall only examines the last N potential knocks amongst K ports, sent from a given IP address, then every possible combination of knocks can be bruteforced in just K^N knocks (by taking into account the existence of every permutation as a subsequence within the De Bruijn sequence) instead of the more obvious (K^N)*N knock solution (naively trying each permutation in sequence.)
https://en.wikipedia.org/wiki/De_Bruijn_sequence https://en.wikipedia.org/wiki/De_Bruijn_sequence