There are a ton more vectors in a host LAMP than Ubuntu, openssl, & apache themselves. To start with, are you running a CMS? Do you use plugins for that CMS? Use PHP apps? Even stuff like react & node frameworks can have vulnerabilities. I would bet a ton of money that whatever happened was not a 0 day Ubuntu/Apache hack.
Reducing the surface area is always smart. But keep in mind Ken Thompson might have managed to hide a backdoor for about 10 years: https://foldoc.org/back+door
There are a ton more vectors in a host LAMP than Ubuntu, openssl, & apache themselves. To start with, are you running a CMS? Do you use plugins for that CMS? Use PHP apps? Even stuff like react & node frameworks can have vulnerabilities. I would bet a ton of money that whatever happened was not a 0 day Ubuntu/Apache hack.
Thats the way to go brother, bare minimums
Reducing the surface area is always smart. But keep in mind Ken Thompson might have managed to hide a backdoor for about 10 years: https://foldoc.org/back+door
and the SPECTRE hacks came out, much of the world's hardware seems compromised and seems to have been for a while: https://en.wikipedia.org/wiki/Transient_execution_CPU_vulnerability
lesson learned, trust no one