Is Debian stable secure?

Debian has always been very cautious/deliberate very stable and very trustworthy, and it’s comparably easy to use for the security it provides. Also the community is big, so it’s more likely that somebody notices shenanigans. … On the other hand, no distro is really “secure” by default.

What are Debian security updates?

Debian security team issues updates to packages in the stable release in which they’ve identified problems related to security. Please consult the security pages for information about any security issues identified in bullseye . After that, run apt update followed by apt upgrade .