The Debian Project has announced that the Debian Long Term Support (LTS) Team is taking over security support for Debian 11 now that it is three years old. The LTS Team takes over this responsibility from the Security and Release Teams, which can now focus on the current Debian 12 and soon-to-be-released Debian 13.
Now that the LTS Team has taken over Debian 11 updates, users can continue using it until August 31, 2026. With that said, the announcement recommends that people upgrade their machine to the current stable, Debian 12. This LTS phase will give anyone who needs it time to upgrade more graciously if they have a lot of data that needs backing up, etc. It"s best not to wait until August 2026 to upgrade, though.
While the base packages should continue to be maintained, the Debian Project warns that a few of your packages may not be supported by the LTS Team. To identify any packages that won"t be supported, users can install the debian-security-support package and then run check-support-status presumably from the terminal to get a list of unsupported packages. If you find a critical package that you would like to get support for, you can email debian-lts@lists.debian.org.
If you do have unmaintained packages installed on your system, it"s probably a good idea to remove them from the terminal using the apt remove command preceded by sudo, of course. According to the Debian Wiki, it appears mostly to be game packages that support is being dropped during the LTS period.
While Debian has a reputation for being rock solid, it is also better suited for people more familiar with Linux than total newbies. One of the reasons for this is that upgrading between major versions is done from the command line instead of a graphical tool like Ubuntu or Fedora. If you want to upgrade to Debian 12, check out the DebianUpgrade page in the Debian Wiki for detailed instructions and read very carefully; don"t just skim-read.