CVE-2023-52628

An out-of-bounds write flaw was found in the Linux kernel’s Netfilter functionality. This flaw allows a local user to crash or potentially escalate their privileges on the system.

This issue is fixed in Red Hat Enterprise Linux 9.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

In order to trigger the issue, it requires the ability to create user/net namespaces.

On non-containerized deployments of Red Hat Enterprise Linux 8, you can disable user namespaces by setting user.max_user_namespaces to 0:

echo "user.max_user_namespaces=0" > /etc/sysctl.d/userns.conf

sysctl -p /etc/sysctl.d/userns.conf

On containerized deployments, such as Red Hat OpenShift Container Platform, do not use this mitigation as the functionality is needed to be enabled.