CVE-2019-5736

A flaw was found in the way runc handled system file descriptors when running containers. A malicious container could use this flaw to overwrite contents of the runc binary and consequently run arbitrary commands on the container host system.

The 'docker' package shipped in Red Hat Enterprise Linux 7 Extras bundles 'runc' since 'docker' starting from version 1.12. Both the 'docker' and 'runc' packages are affected by this issue.

The 'docker-latest' package is deprecated as of Red Hat Enterprise Linux 7.5. Customers using this package should update to the latest 'docker' package shipped in Red Hat Enterprise Linux 7 Extras.

OpenShift Container Platform (OCP) versions 3.9 and later use 'docker' version 1.13 in the default configuration but can be configured to use CRI-O as an alternative, which depends on the 'runc' package. OCP versions 3.9 and later should use the updated 'docker' and 'runc' packages shipped in Red Hat Enterprise Linux 7 Extras.

OCP versions 3.4 through 3.7 originally used 'docker' version 1.12 from the Red Hat Enterprise Linux 7 Extras channel. An updated version of 'docker' 1.12 has been delivered to the RPM channels for OCP versions 3.4 through 3.7.

OCP version 3.9 previously shipped a version of 'runc' in it's RPM repository. OCP 3.9 clusters using CRI-O should update 'runc' from the Red Hat Enterprise Linux 7 Extras channel.

Red Hat Enterprise Linux Atomic Host 7 is not affected by this vulnerability as the target runc binaries are stored on a read-only filesystem and cannot be overwritten.

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.

This vulnerability is mitigated on Red Hat Enterprise Linux 7 if SELinux is in enforcing mode. SELinux in enforcing mode is a pre-requisite for OpenShift Container Platform 3.x.