On 2013-10-16 at 04:05 +0000, Viktor Dukhovni wrote:
> - SMTP is not prone to HTTP's cross-site and chosen plaintext attacks,
> no Javascript in pages served by HTTP servers directing clients to
> other SMTP servers... BEAST, CRIME, ... are HTTPS attacks not generic
> TLS attacks.
Not true.
Given a client system A which is configured to send email through a
server B with SMTP AUTH, the BEAST/CRIME/... attacks can be used in a
message-body to discern the content of the SMTP AUTH. So, *if* SASL
PLAIN is being used, and the client system A can send emails under an
attacker's control (eg, automated monitoring system emails logging
attack events), and the attacker can see the encrypted traffic, then the
authentication credentials can be recovered.
-Phil
