Security update for kvm

Announcement ID: SUSE-SU-2018:1389-1
Rating: important
References:
Cross-References:
CVSS scores:
  • CVE-2018-3639 ( SUSE ): 4.3 CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
  • CVE-2018-3639 ( NVD ): 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
  • CVE-2018-3639 ( NVD ): 5.5 CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected Products:
  • SUSE Linux Enterprise Point of Service 11 SP3
  • SUSE Linux Enterprise Server 11 SP3 LTSS 11-SP3

An update that solves one vulnerability can now be installed.

Description:

This update for kvm fixes the following issues:

This security issue was fixed:

  • CVE-2018-3639: Spectre v4 vulnerability mitigation support for KVM guests (bsc#1092885).

Systems with microprocessors utilizing speculative execution and speculative execution of memory reads before the addresses of all prior memory writes are known may allow unauthorized disclosure of information to an attacker with local user access via a side-channel analysis.

This patch permits the new x86 cpu feature flag named "ssbd" to be presented to the guest, given that the host has this feature, and KVM exposes it to the guest as well.

For this feature to be enabled please use the qemu commandline -cpu $MODEL,+spec-ctrl,+ssbd so the guest OS can take advantage of the feature.

spec-ctrl and ssbd support is also required in the host.

Patch Instructions:

To install this SUSE update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Alternatively you can run the command listed for your product:

  • SUSE Linux Enterprise Point of Service 11 SP3
    zypper in -t patch sleposp3-kvm-13621=1
  • SUSE Linux Enterprise Server 11 SP3 LTSS 11-SP3
    zypper in -t patch slessp3-kvm-13621=1

Package List:

  • SUSE Linux Enterprise Point of Service 11 SP3 (i586)
    • kvm-1.4.2-53.20.1
  • SUSE Linux Enterprise Server 11 SP3 LTSS 11-SP3 (s390x x86_64 i586)
    • kvm-1.4.2-53.20.1

References: