InCommon Baseline TLS 1.2

[Richard Frovarp]

On 7/1/21 2:16 AM, Peter Schober wrote:
> * IAM David Bantz <dabantz at alaska.edu> [2021-06-30 23:32]:
>> TLS 1.0 (1999) and TLS 1.1 (2006) are formally deprecated by IETF RFC 8996.
>>
>> These versions lack support for current and recommended cryptographic
>> algorithms and mechanisms, and various government and industry
>> profiles of applications using TLS now mandate avoiding these old TLS
>> versions. TLS version 1.2 became the recommended version for IETF
>> protocols in 2008...
> I don't think the question was whether it was "secure" to keep
> offering TLS 1.0 and/or TLS 1.1. ;)

The question surrounding a B in SSL Labs and whether or not it is secure 
is basically the same thing. The baseline expectation is:

"Each Identity Provider and Service Provider will secure its connection 
endpoints with current and trusted encryption (TLS)"


The quick and easy way to tell if you probably meet that is to test with 
SSL Labs and get an A.


>
>> Web sites that negotiate a TLS 1.0 or 1.1 protocol will trigger user
>> warnings that connections are “not secure” from Chrome and other browsers.
>  From modern releases of those browsers, maybe. And I'm not convinved
> even that's true: You're saying a modern Chrome or FF release will
> warn even if the server in question also speaks an accaptable TLS
> version? (I've certainly never encountered that myself.)

Yes, evergreen browsers will do this when the server negotiates TLSv1.0 
or TLSv1.1 with the browser. In theory it is possible for a server that 
supports TLSv1.2 to actually negotiate TLSv1.[10]. Either the server is 
misconfigured, or through a downgrade attack. There was a downgrade 
attack in one of the previous version of TLS. I don't believe that there 
is a known downgrade attack in TLSv1.2. Connect to a RHEL5 box, and you 
will be treated to a pretty big warning in both Chrome and Firefox. I 
think both projects planned on dumping TLSv1.0 and TLSv1.1 code from 
their projects last year, so connections would fail like they do against 
something only offering SSLv3. These plans were delayed due to pandemic. 
Browser makers are tired of waiting for systems administrators to update 
their systems.

So they aren't actively making the extra checks, but will warn very 
loudly or just fail when they stumble upon something less than TLSv1.2.

Richard