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2d
comment Are SHA-2 certificates considered obsolete, or current?
(continued) The real reason for the panic is that if an attacker can create a collision affecting a CA certificate, the whole browser PKI house of cards will collapse (or at least collapse even more than previous CA compromises have caused it to do). This is why the browser vendors are so keen to move everything to SHA-2, an attack on a single SHA-1 browser CA cert will break the entire browser PKI. For everyone and everything else, it's much, much less serious.
2d
comment Are SHA-2 certificates considered obsolete, or current?
I've just had to write a document in response to the SHA-1 panic that looks at the possible real-world effects when used with certs. For browser PKI, it's mostly a non-issue, your server switches from a SHA-1 cert to a SHA-2 cert, your browser accepts it as before (and at some point will reject the SHA-1 cert), and all is fine. For client auth, an attacker would need to be able to forge the auth (create a collision) in real-time, so even the more or less totally broken MD5 is fine, the cert forgery that was done there used a huge amount of precomputation.
2d
comment Taxonomy of Ciphers/MACs/Kex available in SSH?
The downside with Blowfish is that it has a very slow key setup. If it's a newer system with AES crypto support in hardware then you may find that the AES variants are now a lot faster. This information wouldn't have been so relevant when the question was originally asked because AES support was less widespread.
Aug
16
comment How secure is the SRP that Blizzard uses to protect passwords?
pepe: John the Ripper now includes support for Blizzards version of SRP :-). @curiousguy: Generally in the five-figure range. Also most HSMs are intended for secure key storage and are pretty slow. You can get crypto accelerators from companies like Cavium, but they're also pretty expensive, you'd need to do custom programming to use them against SRP, and they're designed to speed up particular protocols like TLS and IPsec, so if you're not wanting to do offload of those then things get a lot less fun.
Mar
21
answered Taxonomy of Ciphers/MACs/Kex available in SSH?
Aug
30
awarded  Teacher
Aug
30
answered Vulnerabilities of RFID Smartcards