I have a question regarding NTLMv2 resistance to password bruteforcing.
I know that some modern graphic processors (like Radeon 6990) are able to calculate billions hashes per second and crack NTLM hashes within minutes and hours.
I would like to evaluate how NTLMv2 hashes are more resistant to password bruteforcing comparing to NTLM.
Given that roughly:
NTLM hash = MD4(password)
NTLMv2 hash = MD5(MD5(MD4(password) + X) + Y)
Is it correct to say that attacking NTLMv2 hashes via password bruteforcing is just 3 times longer than attacking NTLM hashes?