RHSA-2018:1396 - Security Advisory

Topic

An update for libvirt is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Low. 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 libvirt library contains a C API for managing and interacting with the virtualization capabilities of Linux and other operating systems. In addition, libvirt provides tools for remote management of virtualized systems.

Security Fix(es):

• libvirt: Resource exhaustion via qemuMonitorIORead() method (CVE-2018-5748)
• libvirt: Incomplete fix for CVE-2018-5748 triggered by QEMU guest agent (CVE-2018-1064)

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.

The CVE-2018-1064 issue was discovered by Daniel P. Berrangé (Red Hat) and the CVE-2018-5748 issue was discovered by Daniel P. Berrange (Red Hat) and Peter Krempa (Red Hat).

Bug Fix(es):

• Previously, the check for a non-unique device boot order did not properly handle updates of existing devices when a new device was attached to a guest. Consequently, updating any device with a specified boot order failed. With this update, the duplicity check detects correctly handles updates and ignores the original device, which avoids reporting false conflicts. As a result, updating a device with a boot order succeeds. (BZ#1557922)
• In Red Hat Enterprise Linux 7.5, guests with SCSI passthrough enabled failed to boot because of changes in kernel CGroup detection. With this update, libvirt fetches dependencies and adds them to the device CGroup. As a result, and the affected guests now start as expected. (BZ#1564996)
• The VMX parser in libvirt did not parse more than four network interfaces. As a consequence, the esx driver did not expose more than four network interface cards (NICs) for guests running ESXi. With this update, the VMX parser parses all the available NICs in .vmx files. As a result, libvirt reports all the NICs of guests running ESXi. (BZ#1566524)
• Previously, user aliases for PTY devices that were longer than 32 characters were not supported. Consequently, if a domain included a PTY device with a user alias longer than 32 characters, the domain would not start. With this update, a static buffer was replaced with a dynamic buffer. As a result, the domain starts even if the length of the user alias for a PTY device is longer than 32 characters. (BZ#1566525)

Solution

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

https://access.redhat.com/articles/11258

After installing the updated packages, libvirtd will be restarted automatically.

Affected Products

• Red Hat Enterprise Linux Server 7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.5 x86_64
• Red Hat Enterprise Linux Server - AUS 7.7 x86_64
• Red Hat Enterprise Linux Server - AUS 7.6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 7 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.5 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.5 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Virtualization 4 for RHEL 7 x86_64
• Red Hat Gluster Storage Server for On-premise 3 for RHEL 7 x86_64
• Red Hat Virtualization for IBM Power LE 4 for RHEL 7 ppc64le
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.5 ppc64le
• Red Hat Enterprise Linux Server - TUS 7.7 x86_64
• Red Hat Enterprise Linux Server - TUS 7.6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x
• Red Hat Enterprise Linux for ARM 64 7 aarch64
• Red Hat Enterprise Linux for Power 9 7 ppc64le
• Red Hat Enterprise Linux EUS Compute Node 7.7 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.6 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.5 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.7 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.6 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.6 x86_64
• Red Hat Enterprise Linux for IBM System z (Structure A) 7 s390x
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le

Fixes

• BZ - 1528396 - CVE-2018-5748 libvirt: Resource exhaustion via qemuMonitorIORead() method
• BZ - 1550672 - CVE-2018-1064 libvirt: Incomplete fix for CVE-2018-5748 triggered by QEMU guest agent
• BZ - 1557922 - Cannot modify vNIC profile of running VM [rhel-7.5.z]
• BZ - 1564996 - Start VM with direct LUN attached with SCSI Pass-Through enabled fails on libvirtError [rhel-7.5.z]
• BZ - 1566524 - vmx parser cannot import more than 4 NICs [rhel-7.5.z]
• BZ - 1566525 - Hosted Engine VM (deployed in the past) fails to reboot with 'libvirtError: internal error: failed to format device alias for PTY retrieval' due to an error in console device in libvirt XML generated by the engine [rhel-7.5.z]

CVEs

• CVE-2018-1064
• CVE-2018-5748

References

• https://access.redhat.com/security/updates/classification/#low