Can you expand on what middleboxes are?
The nature of TLS is that nobody in the middle is supposed to be able to read what's encrypted, and that either end can detect if traffic they receive has been modified in transit.
Of course this is incompatible with corporate (especially financial) networks where employers have legal/compliance/noseyness reasons to want to make sure their employees aren't doing things they shouldn't (sending corporate secrets to the NYT, having their corporate knowledge siphoned out by malware, spending all their time on Facebook etc.), and repressive regimes (where, for example, Erdogan wants to know if you're a member of the Gulen movement) - Bluecoat and Cisco, for example, do a lot of business in the Middle East and China.
They'll typically act as a man in the middle for TLS traffic, re-encrypting traffic using either a compliant root CA or a corporate CA that all employee machines have been made to trust. The nature of Enterprise Software is that these devices will have poor, incomplete or outdated implementations of TLS with the result that, for example, a lot of them didn't know what to do with draft TLS v1.3 traffic and just dropped it on the floor as invalid.
In essence: if corporate wants to spy on me, they shall provide me with devices that are set up that way, and with that I know I can't have any expectation of privacy. If I'm using my own device, I want TLS to actually provide security and confidentiality. If that means denying my personal devices access to the corporate network, so be it.
> Our IT team is going to have to do some work and expose that traffic is sent unencrypted (or differently encrypted) to the final hop on the network.
I get why IT teams don't want to, especially for huge organizations, but "lol we can MITM TLS" is not acceptable. Terminate the exterior TLS at the network, inspect / log it, then re-black it to the end device.
Also, I want to take a second to complain about locally installed certs. I know we all know how they work and everything, but most users don't. The fact that I can see a green lock for google.com when Eve has put a local cert on my machine is really stupid.
People check their personal email on their work computers, that's just a fact of life. Their personal email password shouldn't be in some network log somewhere without them understanding that this is possible. There should be a different colour for when trust is different. A blue lock, for example. I know IT has root anyway, but most companies don't install key loggers on their gear or do obviously shady shit, and I think it would benefit users to have a clear demarcation about who they are trusting.
Looking at the Lewandowski stuff, that's what Google does. And for obvious reasons. Just logging internet traffic isn't very useful at all for compliance.
And maybe it should be country-smart too. An HTTPS cert originating from China and being used for a Chinese service is green, but as the internet balkanizes we may want to be a little smarter. Not sure on that though.
Well, that's their dumbass fault.
At our company, there is a giant warning on the login screen that "You are using a corporate asset and there is NO expectation of privacy."
Now, as to the safety of browser locks... sounds great until the company patches their Firefox distribution.
As you say, there are other issues in a BYOD environment but is that common in an environment that uses middleboxes anyway?
The problem with middleboxes and TLS v1.3 wasn't that IT can see you're on Google, it's that you go to Google and get a grey page that says LOL_SSL_ERROR.
More like, everybody is offline as the middlebox crashed. Which is how it should be: Garbage in the network path should be highlighted and removed.
That's how middleboxes work already. How could they work any other way? If you don't install the root certificate on the client machine TLS fails as it should. You'd need some generally accepted CA to issue a wildcard certificate for the whole internet if that wasn't the case. Has anyone actually done this?
Do you know what traffic your IoT "smart" things and even your PCs and mobile devices is sending and receiving?
Anti-Gülenist cleanup has been completed. It is now the time to appeal and correct the mistakes.
TLS offers end-to-end encryption but a true proxy splits things so that you've got two end-to-end channels with the proxy in the middle. This is fine, Alice talks to the Proxy, the Proxy talks to Bob. All fine.
But of course proxying sixty employees watching funny cat videos on YouTube needs lots of CPU power, which costs money, which means less profits for the middlebox vendors.
So middleboxes pull all sorts of shenanigans rather than actually act as a proxy. For example one trick is pass things through at first, eavesdropping but not actually proxying, then if the middlebox decides things are OK just stop eavesdropping and use a hardware fast path, otherwise drop the connection (wasting resources for both server and client) and when it's retried intercept the retry...
If you imagine this is a Black Hat talk you can probably fill in for yourself all sorts of hilarious things the bad guys might do here with this not-a-proxy.
So that's why this is a terrible outcome from a security point of view. But from a protocol agility point of view it's worse. The middleboxes make all sorts of arbitrary assumptions in their frantic attempts to avoid doing actual work and a working protocol needs to cope with every one of those assumptions or break those middleboxes.
Several big famous middlebox vendors shipped new firmware to make them "ready" for TLS 1.3. What that firmware does is make them TLS 1.2 full proxies. This has two consequences:
1. They now work. Both halves of the proxied connection are TLS 1.2, which works just fine as described above. As a full proxy when a client says "I want TLS 1.3" they can honestly say "Alas I only know TLS 1.2" and so there's no new considerations. So long as they proxy everything.
2. They have intolerably poor performance and will be quietly disabled outside of high threat environments. These boxes haven't anywhere near the brute power needed to really do TLS 1.2 proxy at line rate. Today's web is mostly encrypted, so everything slows to a crawl. The vendor upgrade docs explain how to "mitigate" this slowness by basically disabling the system.