Security vulnerability: CVE-2022-0185 kernel local root exploit and container escape

This document (000020565) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 15 Service Pack 3
SUSE Linux Enterprise Server 15 Service Pack 2

Situation

Researchers have identified a vulnerability in the Linux kernel that could be exploited by local attackers to gain root access and/or escaping containers.

Resolution

Fixed kernel packages have been released, please use

zypper lp -a --cve=CVE-2022-0185

to locate the respective patch name to update.

Cause

The cause is an integer underflow in fsconfig() legacy parameter handling.

Status

Security Alert

Additional Information

If an immediate update is not possible, a workaround is to disable unprivileged user namespaces.
Please note that this could potentially break valid functionality in the system.

On a running system, either restrict the total amount of user-namespaces to 0:

sysctl -w user.max_user_namespaces=0

The described mitigation is not permanent. If the setting needs to be reboot persistent,
add them to /etc/sysctl.conf or one of its included files.

References:

CVE Page:
https://www.suse.com/security/cve/CVE-2022-0185.html

Disclaimer

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