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Google Finds Vulnerability In SSL 3.0 Web Encryption
AlbanX sends word that security researchers from Google have published details on a vulnerability in SSL 3.0 that can allow an attacker to calculate the plaintext of encrypted communications. Google's Bodo Moller writes,
SSL 3.0 is nearly 15 years old, but support for it remains widespread. Most importantly, nearly all browsers support it and, in order to work around bugs in HTTPS servers, browsers will retry failed connections with older protocol versions, including SSL 3.0. Because a network attacker can cause connection failures, they can trigger the use of SSL 3.0 and then exploit this issue. Disabling SSL 3.0 support, or CBC-mode ciphers with SSL 3.0, is sufficient to mitigate this issue, but presents significant compatibility problems, even today. Therefore our recommended response (PDF) is to support TLS_FALLBACK_SCSV. This is a mechanism that solves the problems caused by retrying failed connections and thus prevents attackers from inducing browsers to use SSL 3.0. It also prevents downgrades from TLS 1.2 to 1.1 or 1.0 and so may help prevent future attacks.
Too bad Google removed the options to enable or disable SSL versions from Chrome some time ago, in an effort to further dumb down the browser. The options used to be under "advanced, but they aren't anymore. Not even available under about:flags.
I have a million other things to deal with.
I'll just run my shit against https://www.ssllabs.com/ssltes... in a month and do what it tells me to.
The last major browser that doesn't support TLS 1 was IE6. Even Microsoft doesn't support that piece of crap anymore. I'm sure there's some special cases of embedded systems out there that rely on SSL3 only, but that's a small minority.
So the question to me is, what would break if you disabled SSL3? Breaking the web for IE6 users happened a long, long time ago.
AccountKiller
Become a sesquipedalian - use fancy fonts, Bold, ALL CAPS, whatever it takes to be plaintext free!
This issue is a bit more complicated than you think.
If it doesn't support TLS 1, it isn't worth supporting.
Too bad Google removed the options to enable or disable SSL versions from Chrome some time ago, in an effort to further dumb down the browser. The options used to be under "advanced, but they aren't anymore. Not even available under about:flags.
Still available, but more hidden:
Chrome users that just want to get rid of SSLv3 can use the command line flag --ssl-version-min=tls1 to do so. (We used to have an entry in the preferences for that but people thought that “SSL 3.0” was a higher version than “TLS 1.0” and would mistakenly disable the latter.)
https://www.imperialviolet.org/2014/10/14/poodle.html
Does anyone know what exactly "many clients implement a protocol downgrade dance" means? ... never heard of this ever... who exactly is doing this and what the hell are they thinking?
Screw this TLS_FALLBACK_SCSV bullshit it's 2014 cut the music and send the dancers home.
I think of Alanis here:
Isn't it ironic -- that the very bug the found supports the implementation of the rfc they wrote?
Why would anyone attempt to do this exploit this? It is soo much easier just to get someone to click on a link and snarf up all their data with malware. Why do this 256 try to get 1 byte of a cookie?
From agl:
"Chrome Users Dumbed Down" might have been a more apt title.
Search SSL in Slashdot and go back until you hit 2011. Multiple stories that year about this same issue, it's nothing new. Examples:
http://tech.slashdot.org/story/11/09/20/1833232/hackers-break-browser-ssltls-encryption
http://it.slashdot.org/story/11/10/26/0327251/new-attack-tool-exploits-ssl-renegotiation-bug
I am using IE10, it has effect?
www.shg.com.vn
https://kb.radware.com/questions/2730/SSLv3%7B47%7DTLS+1.0+BEAST+vulnerability
SSLv3 and TLS1.0 are much of a muchness,
http://serverfault.com/questions/178561/what-are-the-exact-protocol-level-differences-between-ssl-and-tls
Are other protocols (POP/IMAP/SMTP come to my mind) over SSL affected?
>Websites secured by SHA-1 certificates that expire in 2017 or later, on this version will be treated as ‘Secure, but with minor errors’.
I don't know the overall percentages on the web but I do know that at least one large company with a significant web presence will ONLY order 1-year certs.
IIRC, MarkMonitor announced that they will stop issuing SHA-1 certs. So I'd say that this move is getting the job done (from Google's POV).
Yeah, there are poorly configured servers out there but it's not fair to call this a server problem.
I'm sitting here watching the various groups (Ops, Crytpo, Security, Network, Dev, IT, ...) walking through the problems of dropping support for SSLv3.
It's a much more complicated issue than you're suggesting.
OTOH, there are big changes that are going to happen in the next few days. For example, Akamai is going to block SSLv3, TLS1.0, TLS1.1 unless a customer specifically tells them not to.
Akamai's About page claims,
>Akamai delivers between 15-30% of all Web traffic
They've claimed higher numbers. At last weeks Edge Conference they claimed 40% (or was it 60% ?) -- don't remember.
Game on.
Akamai is now blocking sslv3 'on their network.
A few hours ago, the plan was to do this next week.
Session keys are getting compromised in 32K guesses. 'Trivial' is the word they're using.
Less than 60 seconds worth of traffic is all it takes.
There's a very high chance that in the very near future, the majority of websites you visit are going to refuse SSLv3.
Been listening to a bridge call with Akamai. They're disabling SSLv3, TLS1.0, and TLS1.1 on their network as I type this.
Some major websites have already disabled SSLv3 on their own (i.e. not waiting for the CDNs to do it).
Akamai carries 30%-40% of the web traffic (globally). Their 'About' page says 30% but they were saying 40% at the conference last week.
FWIW, White Hats are reporting live exploits. They're using the word 'trivial'. It takes less than 60 seconds of traffic to bust a session.
Can someone tell me how to get Firefox to say which protocol it's using for any given session? The Security tab has a Technical Details section that mentions "High-grade Encryption" and TLS, but it doesn't say which version of TLS.
Easiest, one-click way to remove vulnerable SSL3 support from Firefox, while still allowing Mozilla to automatically enforce even safer defaults in future updates:
the SSL Version Control add-on.
There's a browser safer than Firefox, it is Firefox, with NoScript
Could this attack on SSL3 be related to how my https connection to Reddit has been terrible the last few weeks?
So Google manages to find a security hole in a SSL 3 that has been around for 15 years and all of a sudden we should get worried? If you look hard enough, your going to find a hole that you thought wasn't there. Just fix it and move along to the next one.
when we talk about google we should not take it easy
seocafe.tk
Why do you mod this guy down? He speaks the truth! Break out of your mindset of needless backward compatibility and upgrade everything and you'll be fine. If you don't believe him, ssllabs and wikipedia have nice charts showing all worthwhile browsers and servers now support TLS 1.2.