RHSA-2021:0395 - Security Advisory

Topic

An update for redhat-virtualization-host is now available for Red Hat Virtualization 4 for Red Hat Enterprise Linux 7.

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.

Description

The redhat-virtualization-host packages provide the Red Hat Virtualization Host. These packages include redhat-release-virtualization-host. Red Hat Virtualization Hosts (RHVH) are installed using a special build of Red Hat Enterprise Linux with only the packages required to host virtual machines. RHVH features a Cockpit user interface for monitoring the host's resources and performing administrative tasks.

Security Fix(es):

• sudo: Heap buffer overflow in argument parsing (CVE-2021-3156)
• dnsmasq: loose address/port check in reply_query() makes forging replies easier for an off-path attacker (CVE-2020-25684)
• dnsmasq: loose query name check in reply_query() makes forging replies easier for an off-path attacker (CVE-2020-25685)
• dnsmasq: multiple queries forwarded for the same name makes forging replies easier for an off-path attacker (CVE-2020-25686)

For more details about the security issue(s), including the impact, a CVSS score, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• When performing an upgrade of the Red Hat Virtualization Host using the command `yum update`, the yum repository for RHV 4.3 EUS is unreachable

As a workaround, run the following command:
`# yum update --releasever=7Server` (BZ#1899378)

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/2974891

Affected Products

• Red Hat Virtualization 4 for RHEL 7 x86_64
• Red Hat Virtualization Host 4 for RHEL 7 x86_64
• Red Hat Virtualization for IBM Power LE 4 for RHEL 7 ppc64le

Fixes

• BZ - 1889686 - CVE-2020-25684 dnsmasq: loose address/port check in reply_query() makes forging replies easier for an off-path attacker
• BZ - 1889688 - CVE-2020-25685 dnsmasq: loose query name check in reply_query() makes forging replies easier for an off-path attacker
• BZ - 1890125 - CVE-2020-25686 dnsmasq: multiple queries forwarded for the same name makes forging replies easier for an off-path attacker
• BZ - 1899378 - rhel-7-server-rhvh-4.3-eus-rpms repo is unavailable
• BZ - 1916111 - Rebase RHV-H 4.3 EUS on RHEL 7.9.z #3
• BZ - 1917684 - CVE-2021-3156 sudo: Heap buffer overflow in argument parsing

CVEs

• CVE-2020-25684
• CVE-2020-25685
• CVE-2020-25686
• CVE-2021-3156

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/security/vulnerabilities/RHSB-2021-001
• https://access.redhat.com/security/vulnerabilities/RHSB-2021-002