Stay alert! Steam accounts are under attack.
Stay alert! Steam accounts are under attack.
They’d likely be upset about this discussion. It’s not about a breach but a simple mistake by someone. Steam does provide information on third-party link openings.
It seems quite similar to something you shared in your profile for a TF2 trade, though you mentioned no items were involved. Since you were banned from VAC and MalwareBytes blocked the site, it likely came from a suspicious source. I believe it could have been something like what you described.
A rule of thumb is that if you're trading or a stranger adds you and wants to chat, never click any links. There's no reason for you to do that at all. There's some few exceptions like if you're discussing a trade on a trading site like TF2 Outpost, but even then check the link properly before clicking. Links can be very deceptive, you say the link was to Imgur, but it could very well have been lmgur(L instead of i). If you're still in doubt, play dumb and tell them there's something specific wrong with it. Once I got added by a guy and he asked me to add a friend of his, and posted a link to the steam profile. It was obviously fake and I even searched for the profile and found nothing. I told him I couldn't find the user or typing it into the browser didn't work, so he posted a new link with a different profile. I did the same thing again and again, I think he stopped talking to me. TL;DR never open links when trading, you don't need it to trade so don't do it, assume everyone is naked dude in a coat that would stab your scrotum without remorse.
Understanding Trading Basics: Verify profiles and links first. New accounts often hide scams. Stay safe.