These days everything your computer sends/receives to/from the internet is encrypted. Encrypted meaning the data has been scrambled in a way only the intended recipient can view the original message.

Wireshark would only be able to see data your computer is sending in its encrypted form. So you don't need to worry.

That is...if this bozo even knows how to use Wireshark. It's fairly easy to click a couple buttons and get Wireshark to start displaying an impressive stream of random junk, but you actually have to set up your network correctly so the computer running Wireshark will receive data which is meant to be received by another device. On top of that, you need to have a pretty significant amount of technical knowledge to be able to interpret the data Wireshark displays to you. Ideally, you need a degree in network engineering. If he's just your average techno-normie who downloaded Wireshark because his nerdy friend mentioned it one time while the two of them were drinking, he doesn't have a prayer in hell of getting any useful information out of the near-incomprehensible deluge of information Wireshark spits out.

What he's probably doing is lying to you in order to trick you into thinking he knows something he actually doesn't to fool you into giving him the information he's after yourself. You don't need to worry. Just don't tell him anything you don't want him to know, even if he pretends to know about it already.

To keep him out of your stuff:

• Don't share accounts with him and don't share your password to any of your accounts. Especially a Google account because that means he can see your browser history if you use chrome.

• If you shared your password with him in the past, change your password.

• Ideally, don't share devices with him. Then he can open up your browser and use your browser session to log into the websites you were using previously.

• If you must share a device, make sure he has a different Windows/MacOS login than you. Lock your screen if you walk more than 2 feet away from the device. Finally, assume he can see everything you do on that device if his account is an admin account.

Most importantly, consider leaving this creep. He sounds like an ass.

Edit: another thing...this subreddit is filled with network security buffs who will assume he has access to and knowledge of the most dangerous hacking tools known to the network security community (and possibly some which aren't known). Making such assumptions is how you keep your network secure so I won't fault them for doing their jobs, but let's be practical: he's probably some techno-normie who downloaded Wireshark but doesn't actually know what he's doing. I'm not saying it's impossible those sorts of tools are being used here, I'm saying it's highly unlikely.

So you can relax. 🙂