What are the privacy risks of exposing IP adresses?

I'm inclined to think that your IP provides powerful cross-reference potential. Imagine someone either buys the data off of all data brokers out there or a law enforcement agency obtains similar kind of data through warrants, etc. They can cross-reference IPs and time-stamps and determine, that you, Joe Blow, age 35, who works at X, volunteers at Y, and lives at 123 main street, browse for some kind of very embarrassing porn every night. It's a drastic example to illustrate the idea, but I don't think it's far-fetched.

This could be taken further by imagining a wider net: say, a large portion of people who have donated to this political candidate or who work for this company browse for that same embarrassing porn every night.

I'm thinking birds-eye view of potential privacy violations here.

If you trust your firewall, it’s less of a worry than exposing your license plate.

If you do something sus, the police can likely request who had which IP at which time and lead them right to your door.

They only expose approximate, not precise, locations, so they shouldn't be a risk like GPS that exposes precise locations?

Be aware, this is VASTLY dependent on your ISP. Smaller ISP's especially DSL based ones in rural areas are notorious for giving almost exact address when you reverse look up it.

My old ISP used to do that. like I had to try super hard to mask my IP if I went somewhere like IRC or Chatango that disclosed the full address to people joining, because if someone wanted to they could have looked up my address down to the house just by following the remote lookup because it would show my address instead of their nearest hub.

Thankfully now it shows me somewhere in NY which I feel a lot more comfortable with, but still don't take for granted that it's only an approximate.

As for actual privacy risks? It really depends on how private you want to get. A reverse lookup will give you your provider, and sometimes as I said above more. And if you have any forwarding enabled they can also try to get through your services using any exploits or misconfigurations you may have.

Additionally, some routers will disclose a worryingly large amount of data if misconfigured, for example ATT modem/routers will give customer information, connected devices(including names) and VOIP phone configurations if you can get the router to think you are a local device or manage to misconfigure the management port to allow external connections. This is all without the requirement of a password/no auth

Theres definitely some risk especially in semi-anonymous forums like Lemmy. For example Lemmy.world is blocking VPNs so they know everyone's IP addresses and given post history etc its very easy to actually identify who's who. Especially now with AI forensics.

That being said, as a security expert, I think it's not always productive for casual people to be obsessed with this and you if you can you should use a VPN or a mobile network which due to how cell towers work is much more anonymous than anything else in practice (datacenter IPs work too as well as TOR but those are blocked in practice)

Depends of where you lives. if you have only 1 house per km² around you and your isp box provide predictable SSID name, you could be easily found as the ip range is per provider.

Google street cars capture also the wifi network around them when taking street photos.

And getting your ip can connect the people directly to your box. A trace route command to this IP could return intermediate equipment of your isp, helping to pinpoint your town or even your street.

it could enable targeted attacks. just use a vpn if you can afford one.

Also my IP changes every time the router restarts, so that's a thing too.

so they shouldn't be a risk like GPS that exposes precise locations?

Yes, they only provide country, province/state and city. As others mentioned if you’re worried about this information get yourself a reliable VPN provider and, route all your devices through said VPN provider, ideally through your router.

When picking a VPN provider it is highly recommended to read their Privacy Policy before signing up, ensure they don’t log data.