Container-Optimized OS
TMA-COS-1.1.7
Ensure noexec option set on /var partition
LowLevel 2Automatedcos
Description
The noexec mount option specifies that the filesystem cannot contain executable binaries. Since the /var filesystem is only intended for services to write data and not execute, set this option to ensure that users cannot run executable binaries from /var.
How it is checked
Audit method: Shell command
shell
if ! findmnt -kn /var >/dev/null 2>&1; then echo compliant; elif findmnt -kn /var | grep -qw -- noexec; then echo compliant; else echo /var' is mounted without noexec'; fi- Expected output
compliant
How it is fixed
Fix method: Guidance or infrastructure patch
Run the following command to remount /var : # mount -o remount,noexec /var /etc is stateless on Container-Optimized OS. Therefore, /etc cannot be used to make these changes persistent across reboots. The steps mentioned above needs to be performed after every boot.
Properties
- Operating systems
- Any
- Tags
- container-optimized-oscos
- Reference
- CIS Google Container-Optimized OS Benchmark v1.2.0 - 1.1.7 Ensure noexec option set on /var partition
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
shell
tmaegis scan --target cos --level 2