A company's attack surface is everything an intruder can reach, from outside or inside, to try to get in: every server exposed to the internet, every application, every user account, every connected laptop or phone, every cloud service and every vendor with access to your systems. The more pieces there are and the less you know about them, the more gaps go unwatched, which is why the work starts with an inventory and closing what isn't needed.
How TecnetOne handles it: Vulnerability Assessment
attack surface management, entry points, external exposure