Upstream information

CVE-2021-28689 at MITRE

Description

x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest kernels run in ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is why Xen was able to use it to implement paravirtualisation, Xen's novel approach to virtualization. In AMD64, Xen had to use a different implementation approach, so Xen does not use ring 1 to support 64-bit guests. With the focus now being on 64-bit systems, and the availability of explicit hardware support for virtualization, fixing speculation issues in ring 1 is not a priority for processor companies. Indirect Branch Restricted Speculation (IBRS) is an architectural x86 extension put together to combat speculative execution sidechannel attacks, including Spectre v2. It was retrofitted in microcode to existing CPUs. For more details on Spectre v2, see: http://xenbits.xen.org/xsa/advisory-254.html However, IBRS does not architecturally protect ring 0 from predictions learnt in ring 1. For more details, see: https://software.intel.com/security-software-guidance/deep-dives/deep-dive-indirect-branch-restricted-speculation Similar situations may exist with other mitigations for other kinds of speculative execution attacks. The situation is quite likely to be similar for speculative execution attacks which have yet to be discovered, disclosed, or mitigated.

SUSE information

Overall state of this security issue: Running

This issue is currently rated as having moderate severity.

CVSS v2 Scores
  National Vulnerability Database
Base Score 2.1
Vector AV:L/AC:L/Au:N/C:P/I:N/A:N
Access Vector Local
Access Complexity Low
Authentication None
Confidentiality Impact Partial
Integrity Impact None
Availability Impact None
CVSS v3 Scores
  National Vulnerability Database SUSE
Base Score 5.5 5.9
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
Access Vector Local Local
Access Complexity Low High
Privileges Required Low None
User Interaction None None
Scope Unchanged Changed
Confidentiality Impact High High
Integrity Impact None None
Availability Impact None None
CVSSv3 Version 3.1 3.1
SUSE Bugzilla entry: 1185104 [NEW]

SUSE Security Advisories:

List of released packages

Product(s) Fixed package version(s) References
SUSE Linux Enterprise Server 12 SP4-ESPOS
  • xen >= 4.11.4_18-2.54.1
  • xen-doc-html >= 4.11.4_18-2.54.1
  • xen-libs >= 4.11.4_18-2.54.1
  • xen-libs-32bit >= 4.11.4_18-2.54.1
  • xen-tools >= 4.11.4_18-2.54.1
  • xen-tools-domU >= 4.11.4_18-2.54.1
Patchnames:
SUSE-SLE-SERVER-12-SP4-ESPOS-2021-1648
SUSE Linux Enterprise Server 12 SP4-LTSS
  • xen >= 4.11.4_18-2.54.1
  • xen-doc-html >= 4.11.4_18-2.54.1
  • xen-libs >= 4.11.4_18-2.54.1
  • xen-libs-32bit >= 4.11.4_18-2.54.1
  • xen-tools >= 4.11.4_18-2.54.1
  • xen-tools-domU >= 4.11.4_18-2.54.1
Patchnames:
SUSE-SLE-SERVER-12-SP4-LTSS-2021-1648
SUSE Linux Enterprise Server for SAP Applications 12 SP4
  • xen >= 4.11.4_18-2.54.1
  • xen-doc-html >= 4.11.4_18-2.54.1
  • xen-libs >= 4.11.4_18-2.54.1
  • xen-libs-32bit >= 4.11.4_18-2.54.1
  • xen-tools >= 4.11.4_18-2.54.1
  • xen-tools-domU >= 4.11.4_18-2.54.1
Patchnames:
SUSE-SLE-SAP-12-SP4-2021-1648
SUSE OpenStack Cloud 9
  • xen >= 4.11.4_18-2.54.1
  • xen-doc-html >= 4.11.4_18-2.54.1
  • xen-libs >= 4.11.4_18-2.54.1
  • xen-libs-32bit >= 4.11.4_18-2.54.1
  • xen-tools >= 4.11.4_18-2.54.1
  • xen-tools-domU >= 4.11.4_18-2.54.1
Patchnames:
SUSE-OpenStack-Cloud-9-2021-1648
SUSE OpenStack Cloud Crowbar 9
  • xen >= 4.11.4_18-2.54.1
  • xen-doc-html >= 4.11.4_18-2.54.1
  • xen-libs >= 4.11.4_18-2.54.1
  • xen-libs-32bit >= 4.11.4_18-2.54.1
  • xen-tools >= 4.11.4_18-2.54.1
  • xen-tools-domU >= 4.11.4_18-2.54.1
Patchnames:
SUSE-OpenStack-Cloud-Crowbar-9-2021-1648


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification.

Product(s) Source package State
HPE Helion OpenStack 8 xen Affected
SUSE CaaS Platform 4.0 xen Affected
SUSE Enterprise Storage 6 xen Affected
SUSE Linux Enterprise High Performance Computing 12 SP5 xen Affected
SUSE Linux Enterprise High Performance Computing 15 LTSS xen Affected
SUSE Linux Enterprise High Performance Computing 15 SP1 LTSS xen Affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 xen Affected
SUSE Linux Enterprise Module for Server Applications 15 SP2 xen Affected
SUSE Linux Enterprise Point of Service 11 SP3 xen Affected
SUSE Linux Enterprise Server 11 SP4 LTSS xen Affected
SUSE Linux Enterprise Server 12 SP2 BCL xen Affected
SUSE Linux Enterprise Server 12 SP2 LTSS ERICSSON xen Affected
SUSE Linux Enterprise Server 12 SP2 LTSS SAP xen Affected
SUSE Linux Enterprise Server 12 SP3 BCL xen Affected
SUSE Linux Enterprise Server 12 SP3 ESPOS xen Affected
SUSE Linux Enterprise Server 12 SP3 LTSS xen Affected
SUSE Linux Enterprise Server 12 SP4 ESPOS xen Released
SUSE Linux Enterprise Server 12 SP4 LTSS xen Released
SUSE Linux Enterprise Server 12 SP5 xen Affected
SUSE Linux Enterprise Server 15 LTSS xen Affected
SUSE Linux Enterprise Server 15 SP1 Business Critical Linux xen Affected
SUSE Linux Enterprise Server 15 SP1 LTSS xen Affected
SUSE Linux Enterprise Server ESPOS 15 xen Affected
SUSE Linux Enterprise Server for SAP Applications 12 SP3 xen Affected
SUSE Linux Enterprise Server for SAP Applications 12 SP4 xen Released
SUSE Linux Enterprise Server for SAP Applications 12 SP5 xen Affected
SUSE Linux Enterprise Server for SAP Applications 15 xen Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 xen Affected
SUSE Manager Proxy 4.0 xen Affected
SUSE Manager Retail Branch Server 4.0 xen Affected
SUSE Manager Server 4.0 xen Affected
SUSE OpenStack Cloud 8 xen Affected
SUSE OpenStack Cloud 9 xen Released
SUSE OpenStack Cloud Crowbar 8 xen Affected
SUSE OpenStack Cloud Crowbar 9 xen Released