can curl be used to hack a computer?

Can it be used to hack—generally there are a million ways to hack, so potentially yes. However it is not a common vulnerability and I have not heard of anything that is a front burner concern.

There are many back ground operations happening including cURL, I would not be concerned.

https://developer.apple.com/library/content/documentation/MacOSX/Conceptual/BPSy stemStartup/Chapters/DesigningDaemons.ht…

You can read more on cURL from the command line in the Terminal.app, copy and paste:

man curl | more

or legacy write up here: https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPag es/man1/curl.1.html

Lots to read here: https://curl.haxx.se/docs/faq.html

From 2013 http://www.thesafemac.com/chatzum-adware-added-to-vlc-on-softonic/

You can easily run the trusted https://etrecheck.com/ to have a snapshot look at your systems health. Copy and paste the output if you need help interpreting the output.

can curl be used to hack a computer?

More than likely it would be used after a hack to download things to your Mac. But lots of things could be using it legitimately.

The version shipping with High Sierra does have a few vulnerabilities: https://curl.haxx.se/docs/vuln-7.54.0.html

Does Little Snitch say where it was trying to connect to ?.

Do you have any ad blocking extensions installed in Safari?