Following a conversation with a fellow devRanter this came to my mind ago, happened a year or two ago I think.

Was searching for an online note taking app which also provided open source end to end encryption.

After searching for a while I found something that looked alright (do not remember the URL/site too badly). They used pretty good open source JS crypto libraries so it seemed very good!

Then I noticed that the site itself did NOT ran SSL (putting the https:// in front of the site name resulted in site not found or something similar).

Went to the Q/A section because that's really weird.

Saw the answer to that question:

"Since the notes are end to end encrypted client side anyways, we don't see the point in adding SSL. It's secure enough this way".

😵

I emailed them right away explaing that any party inbetween their server(s) and the browser could do anything with the request (includingt the cryptographic JS code) so they should start going onto SSL very very fast.

Too badly I never received a reply.

People, if you ever work with client side crypto, ALWAYS use SSL. Also with valid certs!

The NSA for example has this thing known as the 'Quantum Insert' attack which they can deploy worldwide which basically is an attack where they detect requests being made to servers and reply quickly with their own version of that code which is very probably backdoored.

This attack cannot be performed if you use SSL! (of course only if they don't have your private keys but lets assume that for now)
Luckily Fox-IT (formerly Dutch cyber security company) wrote a Snort (Intrustion Detection System) module for detecting this attack.

Anyways, Always use SSL if you do anything at all with crypto/sensitive data! Actually, always use it but at the very LEAST really do it when you process the mentioned above!

Network Security at it's best at my school.
So firstly our school has only one wifi AP in the whole building and you can only access Internet from there or their PCs which have just like the AP restricted internet with mc afee Webgateway even though they didn't even restrict shuting down computers remotely with shutdown -i.
The next stupid thing is cmd is disabled but powershell isn't and you can execute cmd commands with batch files.
But back to internet access: the proxy with Mcafee is permanently added in these PCs and you don't havs admin rights to change them.
Although this can be bypassed by basically everone because everyone knows one or two teacher accounts, its still restricted right.
So I thought I could try to get around. My first first few tries failed until I found out that they apparently have a mac adress wthitelist for their lan.
Then I just copied a mac adress of one of their ARM terminals pc and set up a raspberry pi with a mac change at startup.
Finally I got an Ip with normal DHCP and internet but port 80 was blocked in contrast to others like 443. So I set up an tcp openvpn server on port 443 elsewhere on a server to mimic ssl traffic.
Then I set up my raspberry pi to change mac, connect to this vpn at startup and provide a wifi ap with an own ip address range and internet over vpn.
As a little extra feature I also added a script for it to act as Spotify connect speaker.
So basically I now have a raspberry pi which I can plugin into power and Ethernet and an aux cable of the always-on-speakers in every room.
My own portable 10mbit/s unrestricted AP with spotify connect speaker.
Last but not least I learnt very many things about networks, vpns and so on while exploiting my schools security as a 16 year old.