RedHat: RHSA-2019-3916:01 Important: OpenShift Container Platform 4.2.5
Summary
Red Hat OpenShift Container Platform is Red Hat's cloud computing
Kubernetes application platform solution designed for on-premise or private
cloud deployments.
This is a text-only advisory for the machine-os-content container image,
which includes RPM packages for Red Hat Enterprise Linux CoreOS.
Security Fix(es):
* A flaw was found in the way Intel CPUs handled inconsistency between
virtual to physical memory address translations in the CPU's local cache
and the system software's Paging structure entries. A privileged guest user
can exploit this flaw to induce a hardware Machine Check Error (MCE) on the
host processor, resulting in a severe DoS scenario by halting the
processor. System software like the OS OR Virtual Machine Monitor (VMM) use
the virtual memory system for storing program instructions and data in
memory. The virtual memory system uses Paging structures like Page Tables
and Page Directories to manage system memory. The processor's Memory
Management Unit (MMU) uses Paging structure entries to translate a
program's virtual memory addresses to physical memory addresses. The
processor stores these address translations into its local cache buffer,
called the Translation Lookaside Buffer (TLB). TLB has two parts, one for
instructions and the other for data addresses. System software can modify
its Paging structure entries to change address mappings or certain
attributes like page size, etc. Upon such Paging structure alterations in
memory, system software must invalidate the corresponding address
translations in the processor's TLB cache. Before this TLB invalidation
takes place, however, a privileged guest user could trigger an instruction
fetch operation, which could use an already cached, but now invalid,
virtual to physical address translation from Instruction TLB (ITLB). This
would access an invalid physical memory address, resulting in halting the
processor due to the MCE on Page Size Change. (CVE-2018-12207)
* A flaw was found in the way sudo implemented running commands with an
arbitrary user ID. If a sudoers entry is written to allow users to run a
command as any user except root, this flaw can be used by an attacker to
bypass that restriction. (CVE-2019-14287)
For more details about the security issue(s), including the impact, a CVSS
score, acknowledgments, and other related information, refer to the CVE
page(s) listed in the References section.
Summary
Solution
See the following documentation, which will be updated shortly for release
4.2.5, for important instructions on how to upgrade your cluster and fully
apply this asynchronous errata update:
https://docs.openshift.com/container-platform/4.2/release_notes/ocp-4-2-release-notes.html
References
https://access.redhat.com/security/cve/CVE-2018-12207 https://access.redhat.com/security/cve/CVE-2019-14287 https://access.redhat.com/security/vulnerabilities/ifu-page-mce https://access.redhat.com/security/updates/classification/#important
Package List
Topic
An update for machine-os-content-container is now available for Red Hat OpenShift Container Platform 4.2.
Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Topic
Relevant Releases Architectures
Bugs Fixed
1646768 - CVE-2018-12207 hw: Machine Check Error on Page Size Change (IFU)
1760531 - CVE-2019-14287 sudo: Privilege escalation via 'Runas' specification with 'ALL' keyword
