Logged in with unknown account apple app store?

I got the alert on my mac that there were updates for my mac in the app store, so I opened the app store and there I got the notice "There are updates for other accounts, Log in with <email> to perform the updates from this account" (translated from Dutch), but the e-mail address in this alert is not my e-mail address nor is it the e-mail address from anybody I know!

I know for a fact that nobody has been on my computer, not by my knowledge at least (and I live alone). How is this possible? Is it possible that this is an error coming from Apple? I'm kind of affraid for the security of my Apple Account and my MacBook.

Thanks.