V-269346

Discussion

Removing support for unneeded filesystem types reduces the local attack surface of the server. A squashfs compressed filesystem image can be mounted without first decompressing the image. Note that Snap packages use squashfs.

Check Content

Verify that AlmaLinux OS 9 disables the ability to load the squashfs kernel module with the following command:

$ grep squashfs /etc/modprobe.conf /etc/modprobe.d/* 

blacklist squashfs

If the command does not return any output, or the line is commented out, and use of squashfs is not documented with the information system security officer (ISSO) as an operational requirement, this is a finding.