Re: Lessons learned disabling SSLv3

[Jeff Borton <jborton () SCHOOLCRAFT EDU>]

Dan,  we have had no harmful fallout by disabling ssl3.  We have roughly 15,000 students per semester.  Just make sure 
your application supports TLS and it is enabled.  There are some new security concerns with TLS 1.0 that you may want 
to research ass well involving poodle.

From: The EDUCAUSE Security Constituent Group Listserv [mailto:SECURITY () LISTSERV EDUCAUSE EDU] On Behalf Of 
Woodruff, Dan
Sent: Tuesday, March 24, 2015 11:48 AM
To: SECURITY () LISTSERV EDUCAUSE EDU
Subject: [SECURITY] Lessons learned disabling SSLv3

We are working to disable SSLv3 in favor of at least TLS1.0 (possibly higher) on all web servers at the University. We 
have some concerns about browser compatibility issues with the versions of TLS. All modern browsers support at least 
TLSv1.0 so we anticipate that the impact to our community will be low if we disabled only SSLv3. If we disabled TLSv1.0 
as well, it seems more browsers would have compatibility issues. Source: 
http://en.wikipedia.org/wiki/Transport_Layer_Security

For systems that are managed by the University, we can make broad configuration changes as needed, but we also have 
students and outside parties with machines not under our control. I'm wondering if other schools have gone through this 
effort to disable SSLv3 and/or TLSv1.0 and have any lessons learned or unexpected consequences they could share?

Thanks in advance,

Dan Woodruff
University IT Security and Policy
University of Rochester