Question re: exterior faucet

So I've got this faucet (hose bib?) out front of our house that seems to have suddenly sprung a leak- there are now 'vents' around the faucet that I don't recall being there. A neighbor had said he saw our faucet suddenly start spraying water, so we shut it off using the valve. I should note we had an attachment at the end that we've since removed- a brass fixture that made it much easier to control the water flow, just screws off the end. Unsure of the name.

We haven't yet winterized our pipes (hasn't been overly cold yet but we're taking care of it tonight anyway), but I've never seen this happen. My limited research leads me to believe this may be some kind of release or backflow preventer that got tripped.

I'm curious if it can be 'reset' or if it needs replacing.

Any insight would be appreciated!

Looks like a backflow preventor. If you have a build up of pressure, it will spray out the sides. Make sure it can flow unrestricted to full pressure, and see if the flow corrects. If not, replacement is recommended.

Back flow preventer froze with attachment on it. Completely destroyed the part. Remove and replace with new backflow preventer. Remember to always remove any hoses or adapters from the backflow preventer prior to any weather near freezing.