CVE-2020-11739

Upstream information

CVE-2020-11739 at MITRE

Description

An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-table ones), so a malicious guest could exploit the race. For instance, there is a small window where Xen can leak memory if XENMAPSPACE_grant_table is used concurrently. A malicious guest may be able to leak memory, or cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded.

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SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having important severity.

CVSS v2 Scores

	National Vulnerability Database
Base Score	6.9
Vector	AV:L/AC:M/Au:N/C:C/I:C/A:C
Access Vector	Local
Access Complexity	Medium
Authentication	None
Confidentiality Impact	Complete
Integrity Impact	Complete
Availability Impact	Complete

CVSS v3 Scores

	National Vulnerability Database
Base Score	7.8
Vector	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Access Vector	Local
Access Complexity	High
Privileges Required	Low
User Interaction	None
Scope	Changed
Confidentiality Impact	High
Integrity Impact	High
Availability Impact	High
CVSSv3 Version	3.1

SUSE Bugzilla entry: 1168142 [NEW]

SUSE Security Advisories:

• SUSE-IU-2020:117-1, published Mon Dec 14 03:22:53 MST 2020
• SUSE-SU-2020:1124-1, published Tue Apr 28 04:19:52 MDT 2020
• SUSE-SU-2020:1138-1, published Wed Apr 29 10:28:02 MDT 2020
• SUSE-SU-2020:1139-1, published Wed Apr 29 11:04:22 MDT 2020
• SUSE-SU-2020:1630-1, published Tue Jun 16 13:12:19 MDT 2020
• SUSE-SU-2020:1634-1, published Wed Jun 17 07:12:54 MDT 2020
• SUSE-SU-2020:2234-1, published Thu Aug 13 07:18:25 MDT 2020
• openSUSE-SU-2020:0599-1, published Sat, 2 May 2020 00:40:00 +0200 (CEST)

List of released packages

Product(s)	Fixed package version(s)	References
HPE Helion Openstack 8	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: HPE-Helion-OpenStack-8-2020-1630
Image SLES15-EC2-CHOST-HVM-BYOS	xen-libs >= 4.10.4_10-3.31.1 xen-tools-domU >= 4.10.4_10-3.31.1
Image SLES15-SP1-CHOST-BYOS-EC2	xen-libs >= 4.12.2_04-3.15.1 xen-tools-domU >= 4.12.2_04-3.15.1
SUSE Enterprise Storage 5	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: SUSE-Storage-5-2020-1630
SUSE Linux Enterprise High Performance Computing 15-ESPOS SUSE Linux Enterprise High Performance Computing 15-LTSS	xen >= 4.10.4_10-3.31.1 xen-devel >= 4.10.4_10-3.31.1 xen-libs >= 4.10.4_10-3.31.1 xen-tools >= 4.10.4_10-3.31.1 xen-tools-domU >= 4.10.4_10-3.31.1	Patchnames: SUSE-SLE-Product-HPC-15-2020-1634
SUSE Linux Enterprise Module for Basesystem 15 SP1	xen-libs >= 4.12.2_04-3.15.1 xen-tools-domU >= 4.12.2_04-3.15.1	Patchnames: SUSE-SLE-Module-Basesystem-15-SP1-2020-1124
SUSE Linux Enterprise Module for Basesystem 15 SP2	xen-libs >= 4.13.1_02-1.2 xen-tools-domU >= 4.13.1_02-1.2
SUSE Linux Enterprise Module for Basesystem 15 SP3	xen-libs >= 4.14.1_16-1.6 xen-tools-domU >= 4.14.1_16-1.6
SUSE Linux Enterprise Module for Open Buildservice Development Tools 15 SP1	xen >= 4.12.2_04-3.15.1 xen-devel >= 4.12.2_04-3.15.1 xen-doc-html >= 4.12.2_04-3.15.1 xen-libs >= 4.12.2_04-3.15.1 xen-libs-32bit >= 4.12.2_04-3.15.1 xen-tools >= 4.12.2_04-3.15.1 xen-tools-domU >= 4.12.2_04-3.15.1	Patchnames: SUSE-SLE-Module-Development-Tools-OBS-15-SP1-2020-1124
SUSE Linux Enterprise Module for Server Applications 15 SP1	xen >= 4.12.2_04-3.15.1 xen-devel >= 4.12.2_04-3.15.1 xen-tools >= 4.12.2_04-3.15.1	Patchnames: SUSE-SLE-Module-Server-Applications-15-SP1-2020-1124
SUSE Linux Enterprise Module for Server Applications 15 SP2	xen >= 4.13.1_02-1.2 xen-devel >= 4.13.1_02-1.2 xen-tools >= 4.13.1_02-1.2 xen-tools-xendomains-wait-disk >= 4.13.1_02-1.2
SUSE Linux Enterprise Module for Server Applications 15 SP3	xen >= 4.14.1_16-1.6 xen-devel >= 4.14.1_16-1.6 xen-tools >= 4.14.1_16-1.6 xen-tools-xendomains-wait-disk >= 4.14.1_16-1.6
SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT	xen >= 4.7.6_08-43.64.1 xen-doc-html >= 4.7.6_08-43.64.1 xen-libs >= 4.7.6_08-43.64.1 xen-libs-32bit >= 4.7.6_08-43.64.1 xen-tools >= 4.7.6_08-43.64.1 xen-tools-domU >= 4.7.6_08-43.64.1	Patchnames: SUSE-SLE-POS-12-SP2-CLIENT-2020-2234
SUSE Linux Enterprise Server 12 SP2-BCL	xen >= 4.7.6_08-43.64.1 xen-doc-html >= 4.7.6_08-43.64.1 xen-libs >= 4.7.6_08-43.64.1 xen-libs-32bit >= 4.7.6_08-43.64.1 xen-tools >= 4.7.6_08-43.64.1 xen-tools-domU >= 4.7.6_08-43.64.1	Patchnames: SUSE-SLE-SERVER-12-SP2-BCL-2020-2234
SUSE Linux Enterprise Server 12 SP2-ESPOS	xen >= 4.7.6_08-43.64.1 xen-doc-html >= 4.7.6_08-43.64.1 xen-libs >= 4.7.6_08-43.64.1 xen-libs-32bit >= 4.7.6_08-43.64.1 xen-tools >= 4.7.6_08-43.64.1 xen-tools-domU >= 4.7.6_08-43.64.1	Patchnames: SUSE-SLE-SERVER-12-SP2-ESPOS-2020-2234
SUSE Linux Enterprise Server 12 SP2-LTSS	xen >= 4.7.6_08-43.64.1 xen-doc-html >= 4.7.6_08-43.64.1 xen-libs >= 4.7.6_08-43.64.1 xen-libs-32bit >= 4.7.6_08-43.64.1 xen-tools >= 4.7.6_08-43.64.1 xen-tools-domU >= 4.7.6_08-43.64.1	Patchnames: SUSE-SLE-SERVER-12-SP2-2020-2234
SUSE Linux Enterprise Server 12 SP3-BCL	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: SUSE-SLE-SERVER-12-SP3-BCL-2020-1630
SUSE Linux Enterprise Server 12 SP3-ESPOS	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: SUSE-SLE-SERVER-12-SP3-ESPOS-2020-1630
SUSE Linux Enterprise Server 12 SP3-LTSS	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: SUSE-SLE-SERVER-12-SP3-2020-1630
SUSE Linux Enterprise Server 12 SP4 SUSE Linux Enterprise Server for SAP Applications 12 SP4	xen >= 4.11.3_04-2.23.1 xen-doc-html >= 4.11.3_04-2.23.1 xen-libs >= 4.11.3_04-2.23.1 xen-libs-32bit >= 4.11.3_04-2.23.1 xen-tools >= 4.11.3_04-2.23.1 xen-tools-domU >= 4.11.3_04-2.23.1	Patchnames: SUSE-SLE-SERVER-12-SP4-2020-1138
SUSE Linux Enterprise Server 12 SP5 SUSE Linux Enterprise Server for SAP Applications 12 SP5	xen >= 4.12.2_04-3.11.1 xen-doc-html >= 4.12.2_04-3.11.1 xen-libs >= 4.12.2_04-3.11.1 xen-libs-32bit >= 4.12.2_04-3.11.1 xen-tools >= 4.12.2_04-3.11.1 xen-tools-domU >= 4.12.2_04-3.11.1	Patchnames: SUSE-SLE-SERVER-12-SP5-2020-1139
SUSE Linux Enterprise Server 15-LTSS	xen >= 4.10.4_10-3.31.1 xen-devel >= 4.10.4_10-3.31.1 xen-libs >= 4.10.4_10-3.31.1 xen-tools >= 4.10.4_10-3.31.1 xen-tools-domU >= 4.10.4_10-3.31.1	Patchnames: SUSE-SLE-Product-SLES-15-2020-1634
SUSE Linux Enterprise Server for SAP Applications 12 SP2	xen >= 4.7.6_08-43.64.1 xen-doc-html >= 4.7.6_08-43.64.1 xen-libs >= 4.7.6_08-43.64.1 xen-libs-32bit >= 4.7.6_08-43.64.1 xen-tools >= 4.7.6_08-43.64.1 xen-tools-domU >= 4.7.6_08-43.64.1	Patchnames: SUSE-SLE-SAP-12-SP2-2020-2234
SUSE Linux Enterprise Server for SAP Applications 12 SP3	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: SUSE-SLE-SAP-12-SP3-2020-1630
SUSE Linux Enterprise Server for SAP Applications 15	xen >= 4.10.4_10-3.31.1 xen-devel >= 4.10.4_10-3.31.1 xen-libs >= 4.10.4_10-3.31.1 xen-tools >= 4.10.4_10-3.31.1 xen-tools-domU >= 4.10.4_10-3.31.1	Patchnames: SUSE-SLE-Product-SLES_SAP-15-2020-1634
SUSE Linux Enterprise Software Development Kit 12 SP4	xen-devel >= 4.11.3_04-2.23.1	Patchnames: SUSE-SLE-SDK-12-SP4-2020-1138
SUSE Linux Enterprise Software Development Kit 12 SP5	xen-devel >= 4.12.2_04-3.11.1	Patchnames: SUSE-SLE-SDK-12-SP5-2020-1139
SUSE OpenStack Cloud 7	xen >= 4.7.6_08-43.64.1 xen-doc-html >= 4.7.6_08-43.64.1 xen-libs >= 4.7.6_08-43.64.1 xen-libs-32bit >= 4.7.6_08-43.64.1 xen-tools >= 4.7.6_08-43.64.1 xen-tools-domU >= 4.7.6_08-43.64.1	Patchnames: SUSE-OpenStack-Cloud-7-2020-2234
SUSE OpenStack Cloud 8	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: SUSE-OpenStack-Cloud-8-2020-1630
SUSE OpenStack Cloud Crowbar 8	xen >= 4.9.4_06-3.62.1 xen-doc-html >= 4.9.4_06-3.62.1 xen-libs >= 4.9.4_06-3.62.1 xen-libs-32bit >= 4.9.4_06-3.62.1 xen-tools >= 4.9.4_06-3.62.1 xen-tools-domU >= 4.9.4_06-3.62.1	Patchnames: SUSE-OpenStack-Cloud-Crowbar-8-2020-1630
openSUSE Leap 15.1	xen >= 4.12.2_04-lp151.2.15.1 xen-devel >= 4.12.2_04-lp151.2.15.1 xen-doc-html >= 4.12.2_04-lp151.2.15.1 xen-libs >= 4.12.2_04-lp151.2.15.1 xen-libs-32bit >= 4.12.2_04-lp151.2.15.1 xen-tools >= 4.12.2_04-lp151.2.15.1 xen-tools-domU >= 4.12.2_04-lp151.2.15.1	Patchnames: openSUSE-2020-599
openSUSE Tumbleweed	xen >= 4.15.1_01-1.2 xen-devel >= 4.15.1_01-1.2 xen-doc-html >= 4.15.1_01-1.2 xen-libs >= 4.15.1_01-1.2 xen-libs-32bit >= 4.15.1_01-1.2 xen-tools >= 4.15.1_01-1.2 xen-tools-domU >= 4.15.1_01-1.2 xen-tools-xendomains-wait-disk >= 4.15.1_01-1.2	Patchnames: openSUSE Tumbleweed GA xen-4.15.1_01-1.2

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First public cloud image revisions this CVE is fixed in:

• alibaba/sles-15-sp3-chost-byos-v20210729
• alibaba/sles-15-sp3-chost-byos-v20210827
• amazon/suse-manager-4-2-proxy-byos-v20210924-hvm-ssd-x86_64
• amazon/suse-manager-4-2-server-byos-v20210924-hvm-ssd-x86_64
• amazon/suse-sles-15-sp3-byos-v20210924-hvm-ssd-x86_64
• amazon/suse-sles-15-sp3-chost-byos-v20210729-hvm-ssd-x86_64
• amazon/suse-sles-15-sp3-chost-byos-v20210827-hvm-ssd-x86_64
• amazon/suse-sles-15-sp3-v20210924-ecs-hvm-ssd-x86_64
• amazon/suse-sles-15-sp3-v20210924-hvm-ssd-x86_64
• amazon/suse-sles-hpc-15-sp3-byos-v20210924-hvm-ssd-x86_64
• amazon/suse-sles-sap-15-sp3-byos-v20210924-hvm-ssd-x86_64
• google/sles-15-sp3-byos-v20210812
• google/sles-15-sp3-chost-byos-v20210729
• google/sles-15-sp3-chost-byos-v20210827
• google/sles-15-sp3-sap-byos-v20210812
• google/sles-15-sp3-sap-v20210812
• google/sles-15-sp3-sapcal-v20210812
• google/sles-15-sp3-v20210812
• google/suse-manager-4-2-proxy-byos-v20210812
• google/suse-manager-4-2-server-byos-v20210812
• microsoft/suse-manager-4-2-proxy-byos-v20210924
• microsoft/suse-manager-4-2-server-byos-v20210924
• microsoft/suse-sles-15-sp3-basic-v20210924
• microsoft/suse-sles-15-sp3-byos-v20210924
• microsoft/suse-sles-15-sp3-chost-byos-v20210729
• microsoft/suse-sles-15-sp3-chost-byos-v20210827
• microsoft/suse-sles-15-sp3-hpc-byos-v20210924
• microsoft/suse-sles-15-sp3-hpc-v20210924
• microsoft/suse-sles-15-sp3-v20210924
• microsoft/suse-sles-sap-15-sp3-byos-v20210924
• microsoft/suse-sles-sap-15-sp3-v20210924

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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	In progress
SUSE CaaS Platform 3.0	xen	Not affected
SUSE CaaS Platform 4.0	xen	In progress
SUSE Container as a Service Platform 1.0	xen	Affected
SUSE Container as a Service Platform 2.0	xen	Not affected
SUSE Enterprise Storage 6	xen	In progress
SUSE Linux Enterprise High Performance Computing 12 SP4	xen	Released
SUSE Linux Enterprise High Performance Computing 12 SP5	xen	Released
SUSE Linux Enterprise High Performance Computing 15 LTSS	xen	Released
SUSE Linux Enterprise High Performance Computing 15 SP1 LTSS	xen	In progress
SUSE Linux Enterprise Module for Basesystem 15 SP1	xen	Released
SUSE Linux Enterprise Module for Basesystem 15 SP2	xen	Already fixed
SUSE Linux Enterprise Module for Server Applications 15 SP1	xen	Released
SUSE Linux Enterprise Module for Server Applications 15 SP2	xen	Already fixed
SUSE Linux Enterprise Point of Service Image Server 12 SP2	xen	Released
SUSE Linux Enterprise Server 11 SP4 LTSS	xen	Not affected
SUSE Linux Enterprise Server 12 SP1 LTSS	xen	Not affected
SUSE Linux Enterprise Server 12 SP2 ESPOS	xen	Released
SUSE Linux Enterprise Server 12 SP2 LTSS	xen	Released
SUSE Linux Enterprise Server 12 SP3 ESPOS	xen	In progress
SUSE Linux Enterprise Server 12 SP3 LTSS	xen	Released
SUSE Linux Enterprise Server 12 SP4	xen	Released
SUSE Linux Enterprise Server 12 SP4 ESPOS	xen	In progress
SUSE Linux Enterprise Server 12 SP4 LTSS	xen	In progress
SUSE Linux Enterprise Server 12 SP5	xen	Released
SUSE Linux Enterprise Server 15 ESPOS	xen	Released
SUSE Linux Enterprise Server 15 LTSS	xen	In progress
SUSE Linux Enterprise Server 15 SP1 LTSS	xen	In progress
SUSE Linux Enterprise Server BCL 12 SP2	xen	Released
SUSE Linux Enterprise Server BCL 12 SP3	xen	Released
SUSE Linux Enterprise Server Business Critical Linux 15 SP1	xen	In progress
SUSE Linux Enterprise Server for SAP Applications 12 SP2	xen	Released
SUSE Linux Enterprise Server for SAP Applications 12 SP3	xen	Released
SUSE Linux Enterprise Server for SAP Applications 12 SP4	xen	Released
SUSE Linux Enterprise Server for SAP Applications 12 SP5	xen	Released
SUSE Linux Enterprise Server for SAP Applications 15	xen	In progress
SUSE Linux Enterprise Server for SAP Applications 15 SP1	xen	In progress
SUSE Linux Enterprise Software Development Kit 12 SP4	xen	Released
SUSE Linux Enterprise Software Development Kit 12 SP5	xen	Released
SUSE Manager Proxy 4.0	xen	In progress
SUSE Manager Retail Branch Server 4.0	xen	In progress
SUSE Manager Server 4.0	xen	In progress
SUSE OpenStack Cloud 7	xen	Released
SUSE OpenStack Cloud 8	xen	In progress
SUSE OpenStack Cloud 9	xen	In progress
SUSE OpenStack Cloud Crowbar 8	xen	In progress
SUSE OpenStack Cloud Crowbar 9	xen	In progress