The Debian GNU/Linux project has released an updated version of its stable Linux distribution Debian 9 (“stretch”). You must upgrade to get corrections for security problem as this version made a few adjustments for the severe issue found in Debian version 9.8. Debian is a Unix-like (Linux distro) operating system and a distribution of Free Software. It is mainly maintained and updated through the work of many users who volunteer their time and effort. The Debian Project was first announced in 1993 by Ian Murdock.
More about Debian Linux 9.8 released
From the release note:
Please note that the point release does not constitute a new version of Debian 9 but only updates some of the packages included. There is no need to throw away old “stretch” media. After installation, packages can be upgraded to the current versions using an up-to-date Debian mirror.
Those who frequently install updates from security.debian.org won’t have to update many packages, and most such updates are included in the point release.
New installation images will be available soon at the regular locations.
Upgrading an existing installation to this revision can be achieved by pointing the package management system at one of Debian’s many HTTP mirrors. A comprehensive list of mirrors is available at:
How to upgrade Debian 9 from version 9.7 to 9.8
The procedure is as follows. First, note down the current version:
$ lsb_release -a
$ uname -mrs
No LSB modules are available. Distributor ID: Debian Description: Debian GNU/Linux 9.7 (stretch) Release: 9.7 Codename: stretch
Upgrade the Debian Linux system
The installer has been updated to include the fixes incorporated into stable by the point release. You can download updated ISO for full installation too. This stable update added important package corrections and security enhancements to the system. Happy upgrades!