Slirp: potential OOB access due to unsafe snprintf() usages
CVE: CVE-2020-8608
Component: QEMU
CWE: CWE-122
Severity: Important
CVSS v3: 5.6/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Release date: 2020-01-27T00:00:00+00:00

An out-of-bounds heap buffer access flaw was found in the SLiRP networking implementation of the QEMU emulator. This flaw occurs in tcp_emu() routine while emulating IRC and other protocols due to unsafe usage of the snprintf(3) function. A user or process could use this flaw to crash the QEMU process on the host, resulting in a denial of service or potential execution of arbitrary code with privileges of the QEMU process on the host.

Statement: This issue affects user-mode or SLiRP networking implementation of the QEMU emulator. Though qemu-kvm package is built with SLiRP networking support, due to its limitations, it is not used by the virtual machine guests by default.

This issue affects versions of the qemu-kvm package as shipped with Red Hat Enterprise Linux 5, 6, 7, 8 and Red Hat Enterprise Linux Advanced Virtualization 8. Future qemu-kvm package updates for Red Hat Enterprise Linux 6, 7, 8 and Red Hat Enterprise Linux Advanced Virtualization 8 may address this issue.

Red Hat Enterprise Linux 5 is now in Maintenance Support 2 Phase of the support and maintenance life cycle. This issue is currently not planned to be addressed in its future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.

Red Hat OpenStack Platform:                                                                                                                 
This flaw impacts KVM user-mode or SLIRP networking, which is not used in Red Hat OpenStack Platform. Although updating is recommended for affected versions (see below), Red Hat OpenStack Platform environments are not vulnerable.

Remediation:
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.
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.
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.
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.
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.
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.
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.
Before applying this update, ensure all previously released errata relevant
to your system have been applied.

For OpenShift Container Platform 4.3 see the following documentation, which
will be updated shortly for release 4.3.3, for important instructions on
how to upgrade your cluster and fully apply this asynchronous errata
update:

https://docs.openshift.com/container-platform/4.3/release_notes/ocp-4-3-release-notes.html

Details on how to access this content are available at
https://docs.openshift.com/container-platform/4.3/updating/updating-cluster-cli.html.
Before applying this update, make sure all previously released errata
relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/2974891
Before applying this update, make sure all previously released errata
relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/2974891
This issue can only be resolved by applying updates.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.