Re: Terrapin

Peter Gutmann <[email protected]> Sat, 30 Dec 2023 07:05:14 +0000
Newsgroups gmane.ietf.secsh
Message-ID <SY4PR01MB62519A632EDA2D4A25FACDD4EE9CA@SY4PR01MB6251.ausprd01.prod.outlook.com>
Mouse <[email protected]> writes:=0A=0A>I've mentioned my own unde=
rstanding of the reason on-list recently; search=0A>for "SandP" in your bac=
k mail, or the archives if need be. (Most briefly, my=0A>understanding is t=
hat it's to defeat an attack, but in my opinion there are=0A>better defense=
s.)=0A=0AI saw that, but the link posted is 404 (or at least "MySQL error")=
, I assume=0Ait's the Paterson et al paper from 2009?  I can see that, due =
the use of AES-=0ACTR in GCM, an attacker can make you see anything they wa=
nt in the decrypted=0Apacket rather than the CBC alternative where they jus=
t have to hope for the=0Abest (with low probability), but if you've already=
 closed that hole, or never=0Ahad it in the first place, I can't see what d=
ifference it'd make.  From the=0Acode changes I had to make I'd say all the=
 special-snowflake code added to=0Asupport EtM-OpenSSH is probably a much b=
igger issue in terms of attack=0Asurface.=0A=0APeter.