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Red Hat 7 RHSA-2017-0083 Low Severity: qemu-kvm Denial of Service

red hat
Calendar Grey January 17, 2017
Scroller Redhat
Red Hat has issued a minimal-impact security patch for qemu-kvm to resolve an out-of-bounds vulnerability along with additional issues.
An update for qemu-kvm is now available for Red Hat Enterprise Linux 7

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 this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.

Summary

Kernel-based Virtual Machine (KVM) is a full virtualization solution for Linux on AMD64 and Intel 64 systems. The qemu-kvm packages provide the user-space component for running virtual machines using KVM.
Security Fix(es):
* An out-of-bounds read-access flaw was found in the QEMU emulator built with IP checksum routines. The flaw could occur when computing a TCP/UDP packet's checksum, because a QEMU function used the packet's payload length without checking against the data buffer's size. A user inside a guest could use this flaw to crash the QEMU process (denial of service). (CVE-2016-2857)
Red Hat would like to thank Ling Liu (Qihoo 360 Inc.) for reporting this issue.
Bug Fix(es):
* Previously, rebooting a guest virtual machine more than 128 times in a short period of time caused the guest to shut down instead of rebooting, because the virtqueue was not cleaned properly. This update ensures that the virtqueue is cleaned more reliably, which prevents the described problem from occurring. (BZ#1393484)

Topics%20covered

Topics Covered

security advisory denial of service security issue bug fix Red Hat Enterprise Linux low severity qemu-kvm

References

https://access.redhat.com/security/cve/CVE-2016-2857 https://access.redhat.com/security/updates/classification#low https://access.redhat.com/security/updates/classification#Low

Package List

Red Hat Enterprise Linux Client (v. 7):
Source: qemu-kvm-1.5.3-126.el7_3.3.src.rpm
x86_64: qemu-img-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-common-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-debuginfo-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-tools-1.5.3-126.el7_3.3.x86_64.rpm
Red Hat Enterprise Linux ComputeNode Optional (v. 7):
Source: qemu-kvm-1.5.3-126.el7_3.3.src.rpm
x86_64: qemu-img-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-common-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-debuginfo-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-tools-1.5.3-126.el7_3.3.x86_64.rpm
Red Hat Enterprise Linux Server (v. 7):
Source: qemu-kvm-1.5.3-126.el7_3.3.src.rpm
ppc64: qemu-img-1.5.3-126.el7_3.3.ppc64.rpm qemu-kvm-debuginfo-1.5.3-126.el7_3.3.ppc64.rpm
ppc64le: qemu-img-1.5.3-126.el7_3.3.ppc64le.rpm qemu-kvm-debuginfo-1.5.3-126.el7_3.3.ppc64le.rpm
x86_64: qemu-img-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-common-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-debuginfo-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-tools-1.5.3-126.el7_3.3.x86_64.rpm
Red Hat Enterprise Linux Workstation (v. 7):
Source: qemu-kvm-1.5.3-126.el7_3.3.src.rpm
x86_64: qemu-img-1.5.3-126.el7_3.3.x86_64.rpm qemu-kvm-1.5.3-126.el7_3.3.x86_64.rpm

Read the Full Advisory


Severity
low
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2017:0083-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2017:0083.html
Issue date: 2017-01-17

Topic

An update for qemu-kvm is now available for Red Hat Enterprise Linux 7.Red Hat Product Security has rated this update as having a security impactof Low. A Common Vulnerability Scoring System (CVSS) base score, whichgives a detailed severity rating, is available for each vulnerability fromthe CVE link(s) in the References section.

Topics%20covered

Topics Covered

security advisory denial of service security issue bug fix Red Hat Enterprise Linux low severity qemu-kvm

Relevant Releases Architectures

Red Hat Enterprise Linux Client (v. 7) - x86_64

Red Hat Enterprise Linux ComputeNode Optional (v. 7) - x86_64

Red Hat Enterprise Linux Server (v. 7) - ppc64, ppc64le, x86_64

Red Hat Enterprise Linux Workstation (v. 7) - x86_64

Bugs Fixed

1296567 - CVE-2016-2857 Qemu: net: out of bounds read in net_checksum_calculate()

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