Re: [TLS] DTLS cookie and session resumption.
Nikos Mavrogiannopoulos <nmav@redhat.com> Mon, 23 December 2013 12:46 UTC
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From: Nikos Mavrogiannopoulos <nmav@redhat.com>
To: Fabrice Gautier <fabrice.gautier@gmail.com>
Date: Mon, 23 Dec 2013 13:46:35 +0100
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Cc: "<tls@ietf.org>" <tls@ietf.org>
Subject: Re: [TLS] DTLS cookie and session resumption.
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On Fri, 2013-12-20 at 10:25 -0800, Fabrice Gautier wrote: > Is it safe for a DTLS server not to perform a cookie verification and > send a ClientHelloVerifyRequest message if the ClientHello sessionID > point to a session that can be resumed successfully ? > > I'm assuming it's not in general. For example, an attacker could first > perform a full connection, then DDOS the server with resumption > attempts. Or the attacker could sniff one session ID and then flood the server using it. regards, Nikos
- [TLS] DTLS cookie and session resumption. Fabrice Gautier
- Re: [TLS] DTLS cookie and session resumption. Nikos Mavrogiannopoulos
- Re: [TLS] DTLS cookie and session resumption. Martin Thomson