CVE-2020-29567

Upstream information

CVE-2020-29567 at MITRE

Description

An issue was discovered in Xen 4.14.x. When moving IRQs between CPUs to distribute the load of IRQ handling, IRQ vectors are dynamically allocated and de-allocated on the relevant CPUs. De-allocation has to happen when certain constraints are met. If these conditions are not met when first checked, the checking CPU may send an interrupt to itself, in the expectation that this IRQ will be delivered only after the condition preventing the cleanup has cleared. For two specific IRQ vectors, this expectation was violated, resulting in a continuous stream of self-interrupts, which renders the CPU effectively unusable. A domain with a passed through PCI device can cause lockup of a physical CPU, resulting in a Denial of Service (DoS) to the entire host. Only x86 systems are vulnerable. Arm systems are not vulnerable. Only guests with physical PCI devices passed through to them can exploit the vulnerability.

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SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having moderate severity.

CVSS v2 Scores

	National Vulnerability Database
Base Score	4.9
Vector	AV:L/AC:L/Au:N/C:N/I:N/A:C
Access Vector	Local
Access Complexity	Low
Authentication	None
Confidentiality Impact	None
Integrity Impact	None
Availability Impact	Complete

CVSS v3 Scores

	National Vulnerability Database	SUSE
Base Score	6.2	6.5
Vector	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Access Vector	Local	Local
Access Complexity	Low	Low
Privileges Required	None	Low
User Interaction	None	None
Scope	Unchanged	Changed
Confidentiality Impact	None	None
Integrity Impact	None	None
Availability Impact	High	High
CVSSv3 Version	3.1	3.1

SUSE Bugzilla entry: 1179513 [NEW]

No SUSE Security Announcements cross referenced.

List of released packages

Product(s)	Fixed package version(s)	References
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 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

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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-sles-15-sp3-chost-byos-v20210729-hvm-ssd-x86_64
• amazon/suse-sles-15-sp3-chost-byos-v20210827-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-sles-15-sp3-chost-byos-v20210729
• microsoft/suse-sles-15-sp3-chost-byos-v20210827

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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	Not affected
SUSE Enterprise Storage 5	xen	Unsupported
SUSE Linux Enterprise High Performance Computing 12 SP5	xen	Not affected
SUSE Linux Enterprise High Performance Computing 15 LTSS	xen	Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP1	xen	Unsupported
SUSE Linux Enterprise Module for Basesystem 15 SP2	xen	Not affected
SUSE Linux Enterprise Module for Server Applications 15 SP1	xen	Unsupported
SUSE Linux Enterprise Module for Server Applications 15 SP2	xen	Not affected
SUSE Linux Enterprise Point of Service 11 SP3	xen	Not affected
SUSE Linux Enterprise Point of Service Image Server 12	xen	Unsupported
SUSE Linux Enterprise Server 11 SP4 LTSS	xen	Not affected
SUSE Linux Enterprise Server 12 SP2 BCL	xen	Not affected
SUSE Linux Enterprise Server 12 SP2 ESPOS	xen	Unsupported
SUSE Linux Enterprise Server 12 SP2 LTSS	xen	Not affected
SUSE Linux Enterprise Server 12 SP3 BCL	xen	Not affected
SUSE Linux Enterprise Server 12 SP3 ESPOS	xen	Not affected
SUSE Linux Enterprise Server 12 SP3 LTSS	xen	Not affected
SUSE Linux Enterprise Server 12 SP4 ESPOS	xen	Not affected
SUSE Linux Enterprise Server 12 SP4 LTSS	xen	Not affected
SUSE Linux Enterprise Server 12 SP5	xen	Not affected
SUSE Linux Enterprise Server 15 LTSS	xen	Not affected
SUSE Linux Enterprise Server ESPOS 15	xen	Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP2	xen	Unsupported
SUSE Linux Enterprise Server for SAP Applications 12 SP3	xen	Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP4	xen	Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP5	xen	Not affected
SUSE Linux Enterprise Server for SAP Applications 15	xen	Not affected
SUSE OpenStack Cloud 7	xen	Not affected
SUSE OpenStack Cloud 8	xen	Not affected
SUSE OpenStack Cloud 9	xen	Not affected
SUSE OpenStack Cloud Crowbar 8	xen	Not affected
SUSE OpenStack Cloud Crowbar 9	xen	Not affected