Google Prepares Fix To Stop SSL/TLS Attacks 122
OverTheGeicoE writes "It was reported Tuesday that researchers had found a way to break the most commonly used SSL/TLS encryption in browsers. According to the Register, Google is pushing out a patch to fix the problem. The patch doesn't involve adding support for TLS 1.1 or 1.2. FTFA: 'The change introduced into Chrome would counteract these attacks by splitting a message into fragments to reduce the attacker's control over the plaintext about to be encrypted. By adding unexpected randomness to the process, the new behavior in Chrome is intended to throw BEAST off the scent of the decryption process by feeding it confusing information.' The fix is supposedly in the latest developer version of Chrome."
Re:All the more reason to use a VPN (Score:4, Interesting)
I found out all that information for myself separately before you posted that, but it's interesting to see the problem. I had to make the same assumption that the attack described is actually the one that was published all those years ago, which is pretty likely at this stage.
To summarise: Web browsers tend to use the NSS libraries, which have a "bug". The bug is subtle and actually part of the TLS 1.0 standard, but a tiny, standards-compliant, workaround virtually fixes the problem.
It's the same bug that OpenSSL patched 9 YEARS ago, fully knowing what they were patching and based on a publicly available paper on attacking exactly what NSS/OpenSSL were designed for (so the name "Network Security Services" is a bit of a misnomer now). The workaround is pretty basic (throw empty junk into the conversation first) but by all accounts "works".
A lot of browsers use NSS and thus are vulnerable. Some don't and thus aren't (Opera uses OpenSSL which was patched against this 9 years ago!). The "fix" that Google have committed to Chrome is basically identical to the OpenSSL fix from all those years ago.
The bug was pretty much unforeseeable all that time ago, and thus TLS 1.1 etc. were born to supplant it. You can't really blame people for the bug existing in the standard - you CAN blame them for not fixing it 9 years ago when others did exactly that, in "open" code.
Lessons to be learned:
1) SSL library authors needs to READ publicly available exploits aimed at the code they are developing.
2) They need to read other project's bug/commit-logs/security warnings if they are serious about being a competitor to their security.
3) Don't use libraries that don't do the above if you want to be taken seriously, and certainly not in a mainstream millions-of-deployments browser.
4) Update your libraries and recompile your code when they change.
OpenSSL know what they are doing and have a good reputation. NSS are pretty much amateurs. Think of that next time you want to use an SSL library.
Re:TLS 1.1 or 1.2? (Score:2, Interesting)
Will you kindly explain to the unwashed masses how you would implement TLS 1.1 and 1.2 support in a world where the dominant library OpenSSL does not yet support either of the protocols in its stable releases? Sure, you can use GnuTLS and mod_gnutls, and I have tried it, but there was no point, as no browser apart from Opera supported it and there were some weird glitches in the module. IE 8/9 were supposed to support them under Vista and 7, but failed to access the site served by mod_gnutls when 1.1 and 1.2 were enabled on the client side. I tried it anew yesterday just out of curiosity, and now even Opera 11.51 chokes on TLS 1.1 and 1.2. So there. Nothing really supports the protocols. Must wait for OpenSSL 1.0.1 for TLS 1.1 and nobody knows when that will hit the repos.