[lurked_for_a_decade]

17 octets of four hexadecimal number is 172 bits.

There is a 172 bit attack on an AES-256 encryption key.

This “hint” may be the 172 bit attack vector that will hace someones 256 bit AES key.

http://eprint.iacr.org/2009/317
http://eprint.iacr.org/2009/374

Attack complexity based on the two papers:

AES-128 = 126.1 bits
AES-192 = 172 bits
AES-256 = 99.5 bits

[lurked_for_a_decade]

Man in the middle attack on an improperly configured https secured web page. like oh a mail reader, through a bug in the WIFI WPA2 encryption security prrotocol.

https://www.youtube.com/watch?time_continue=126&v=Oh4WURZoR98

[palmer]

There is a 172 bit attack on an AES-256 encryption key.

256 bit AES has a 2^119 attack. As Schneier pointed out https://www.schneier.com/blog/archives/2009/07/another_new_aes.html it is impractical, not a threat to AES.

This attack has nothing to do with whether Assange is or is not revealing a 256 bit (or any size) key. His tweet contains 16 bytes of ascii and 16 bytes of binary. The 16 bytes of binary could be a key, or not. He may have a key and may be revealing it, or not.