Issued:
2019-05-14
Updated:
2019-05-14

RHSA-2019:1197 - Security Advisory

Synopsis

Important: libvirt security update

Type/Severity

Security Advisory: Important

Topic

An update for libvirt is now available for Red Hat Enterprise Linux 6.5 Advanced Update Support.

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 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):

  • A flaw was found in the implementation of the "fill buffer", a mechanism used by modern CPUs when a cache-miss is made on L1 CPU cache. If an attacker can generate a load operation that would create a page fault, the execution will continue speculatively with incorrect data from the fill buffer while the data is fetched from higher level caches. This response time can be measured to infer data in the fill buffer. (CVE-2018-12130)
  • Modern Intel microprocessors implement hardware-level micro-optimizations to improve the performance of writing data back to CPU caches. The write operation is split into STA (STore Address) and STD (STore Data) sub-operations. These sub-operations allow the processor to hand-off address generation logic into these sub-operations for optimized writes. Both of these sub-operations write to a shared distributed processor structure called the 'processor store buffer'. As a result, an unprivileged attacker could use this flaw to read private data resident within the CPU's processor store buffer. (CVE-2018-12126)
  • Microprocessors use a ‘load port’ subcomponent to perform load operations from memory or IO. During a load operation, the load port receives data from the memory or IO subsystem and then provides the data to the CPU registers and operations in the CPU’s pipelines. Stale load operations results are stored in the 'load port' table until overwritten by newer operations. Certain load-port operations triggered by an attacker can be used to reveal data about previous stale requests leaking data back to the attacker via a timing side-channel. (CVE-2018-12127)
  • Uncacheable memory on some microprocessors utilizing speculative execution may allow an authenticated user to potentially enable information disclosure via a side channel with local access. (CVE-2019-11091)

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.

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 - AUS 6.5 x86_64

Fixes

  • BZ - 1646781 - CVE-2018-12126 hardware: Microarchitectural Store Buffer Data Sampling (MSBDS)
  • BZ - 1646784 - CVE-2018-12130 hardware: Microarchitectural Fill Buffer Data Sampling (MFBDS)
  • BZ - 1667782 - CVE-2018-12127 hardware: Micro-architectural Load Port Data Sampling - Information Leak (MLPDS)
  • BZ - 1705312 - CVE-2019-11091 hardware: Microarchitectural Data Sampling Uncacheable Memory (MDSUM)

CVEs

References

Red Hat Enterprise Linux Server - AUS 6.5

SRPM
libvirt-0.10.2-29.el6_5.18.src.rpm SHA-256: fc59781ceab9f94fc4075782e50f147e22e5b624b2706db13f3deb80801611ee
x86_64
libvirt-0.10.2-29.el6_5.18.x86_64.rpm SHA-256: 180191c9f5e9ec3b62762765ec8a63ea9b88b25c30839b82dce009f2ea9df125
libvirt-client-0.10.2-29.el6_5.18.i686.rpm SHA-256: 099075835e55f8024fe33424e2808f7d50d7cb02043a4b0297e1fc946a46bde6
libvirt-client-0.10.2-29.el6_5.18.x86_64.rpm SHA-256: 91bd9fa1c341b2df5587190bb7c8187fb6489855bd394f98290e2b8bbfc91a57
libvirt-debuginfo-0.10.2-29.el6_5.18.i686.rpm SHA-256: 1ce2548c67f0e13c6e51c2c87f1e50d968ae920f4f47a92e7e65ed75960b6497
libvirt-debuginfo-0.10.2-29.el6_5.18.x86_64.rpm SHA-256: 211d40c9af0966eda27490748395ea0eb18e345d378d657f633b72bf6152de05
libvirt-debuginfo-0.10.2-29.el6_5.18.x86_64.rpm SHA-256: 211d40c9af0966eda27490748395ea0eb18e345d378d657f633b72bf6152de05
libvirt-devel-0.10.2-29.el6_5.18.i686.rpm SHA-256: d581abb4b6e7032034ace31cdfc051a12623bf682248f1bf28592500fa6452f7
libvirt-devel-0.10.2-29.el6_5.18.x86_64.rpm SHA-256: 8a89c4bba0ce8aaf4d503c07946601c846e0276637747e5f30c1dc99772f3b35
libvirt-lock-sanlock-0.10.2-29.el6_5.18.x86_64.rpm SHA-256: 3b64d7fff8fef1da2a1dd73e7564c2fdd5587b24d4e855122f6f78188d421ba0
libvirt-python-0.10.2-29.el6_5.18.x86_64.rpm SHA-256: ccfefd08801bfa759d55f5877c176a4d09f6f1e635d14aef5f0bec4abf113f7f

The Red Hat security contact is secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.