Upstream information

CVE-2020-29487 at MITRE

Description

An issue was discovered in Xen XAPI before 2020-12-15. Certain xenstore keys provide feedback from the guest, and are therefore watched by toolstack. Specifically, keys are watched by xenopsd, and data are forwarded via RPC through message-switch to xapi. The watching logic in xenopsd sends one RPC update containing all data, any time any single xenstore key is updated, and therefore has O(N^2) time complexity. Furthermore, message-switch retains recent (currently 128) RPC messages for diagnostic purposes, yielding O(M*N) space complexity. The quantity of memory a single guest can monopolise is bounded by xenstored quota, but the quota is fairly large. It is believed to be in excess of 1G per malicious guest. In practice, this manifests as a host denial of service, either through message-switch thrashing against swap, or OOMing entirely, depending on dom0's configuration. (There are no quotas in xenopsd to limit the quantity of keys that result in RPC traffic.) A buggy or malicious guest can cause unreasonable memory usage in dom0, resulting in a host denial of service. All versions of XAPI are vulnerable. Systems that are not using the XAPI toolstack are not vulnerable.

SUSE information

Overall state of this security issue: Does not affect SUSE products

This issue is currently rated as having moderate severity.

CVSS v2 Scores
  National Vulnerability Database
Base Score 7.8
Vector AV:N/AC:L/Au:N/C:N/I:N/A:C
Access Vector Network
Access Complexity Low
Authentication None
Confidentiality Impact None
Integrity Impact None
Availability Impact Complete
CVSS v3 Scores
  National Vulnerability Database SUSE
Base Score 7.5 6.5
Vector CVSS:3.1/AV:N/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
Attack Vector Network Local
Attack 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: 1179512 [RESOLVED / INVALID]

No SUSE Security Announcements cross referenced.


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Please note that this evaluation state might be work in progress, incomplete or outdated.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. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Micro 5.1 xen Not affected
SUSE Linux Enterprise Micro 5.2 xen Not affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 12 SP5 xen Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2 xen Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS xen Analysis
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS xen Analysis
SUSE Linux Enterprise High Performance Computing 15 SP3 xen Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS xen Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS xen Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 xen Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP3 xen Not affected
SUSE Linux Enterprise Module for Server Applications 15 SP2 xen Not affected
SUSE Linux Enterprise Module for Server Applications 15 SP3 xen Not affected
SUSE Linux Enterprise Server 12 SP5 xen Not affected
SUSE Linux Enterprise Server 12 SP5-LTSS xen Not affected
SUSE Linux Enterprise Server 15 SP2 xen Not affected
SUSE Linux Enterprise Server 15 SP2-LTSS xen Analysis
SUSE Linux Enterprise Server 15 SP3 xen Not affected
SUSE Linux Enterprise Server 15 SP3-LTSS xen Not affected
SUSE Linux Enterprise Server 15-ESPOS xen Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 xen Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP5 xen Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 xen Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 xen Not affected
Products past their end of life and not receiving proactive updates anymore.
HPE Helion OpenStack 8 xen Not affected
SUSE CaaS Platform 3.0 xen Not affected
SUSE CaaS Platform 4.0 xen Not affected
SUSE Enterprise Storage 5 xen Not affected
SUSE Enterprise Storage 6 xen Not affected
SUSE Enterprise Storage 7 xen Not affected
SUSE Enterprise Storage 7.1 xen Not affected
SUSE Linux Enterprise Desktop 11 SP3 xen Not affected
SUSE Linux Enterprise Desktop 11 SP4 xen Not affected
SUSE Linux Enterprise Desktop 12 SP2 xen Not affected
SUSE Linux Enterprise Desktop 12 SP3 xen Not affected
SUSE Linux Enterprise Desktop 12 SP4 xen Not affected
SUSE Linux Enterprise Desktop 15 xen Not affected
SUSE Linux Enterprise Desktop 15 SP1 xen Not affected
SUSE Linux Enterprise Desktop 15 SP2 xen Not affected
SUSE Linux Enterprise Desktop 15 SP3 xen Not affected
SUSE Linux Enterprise High Performance Computing 15 xen Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1 xen Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS xen Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS xen Not affected
SUSE Linux Enterprise High Performance Computing 15-ESPOS xen Not affected
SUSE Linux Enterprise High Performance Computing 15-LTSS xen Not affected
SUSE Linux Enterprise Micro 5.0 xen Unsupported
SUSE Linux Enterprise Module for Basesystem 15 xen Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 xen Not affected
SUSE Linux Enterprise Module for Server Applications 15 xen Not affected
SUSE Linux Enterprise Module for Server Applications 15 SP1 xen Not affected
SUSE Linux Enterprise Point of Sale 11 SP3 xen Not affected
SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT xen Not affected
SUSE Linux Enterprise Point of Service 11 SP3 xen Not affected
SUSE Linux Enterprise Point of Service Image Server 12 SP2 xen Not affected
SUSE Linux Enterprise Real Time 15 SP2 xen Analysis
SUSE Linux Enterprise Real Time 15 SP3 xen Not affected
SUSE Linux Enterprise Server 11 SP3 xen Not affected
SUSE Linux Enterprise Server 11 SP3-LTSS xen Not affected
SUSE Linux Enterprise Server 11 SP4 xen Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS xen Not affected
SUSE Linux Enterprise Server 11 SP4-LTSS xen Not affected
SUSE Linux Enterprise Server 12 SP2 xen Not affected
SUSE Linux Enterprise Server 12 SP2-BCL xen Not affected
SUSE Linux Enterprise Server 12 SP2-ESPOS xen Not affected
SUSE Linux Enterprise Server 12 SP2-LTSS xen Not affected
SUSE Linux Enterprise Server 12 SP3 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 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 15 xen Not affected
SUSE Linux Enterprise Server 15 SP1 xen Not affected
SUSE Linux Enterprise Server 15 SP1-BCL xen Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS xen Not affected
SUSE Linux Enterprise Server 15 SP2-BCL xen Analysis
SUSE Linux Enterprise Server 15 SP3-BCL xen Not affected
SUSE Linux Enterprise Server 15-LTSS xen Not affected
SUSE Linux Enterprise Server for SAP Applications 11 SP3 xen Not affected
SUSE Linux Enterprise Server for SAP Applications 11 SP4 xen Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP2 xen Not affected
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 15 xen Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 xen Not affected
SUSE Linux Enterprise Software Development Kit 11 SP3 xen Not affected
SUSE Linux Enterprise Software Development Kit 11 SP4 xen Not affected
SUSE Linux Enterprise Software Development Kit 12 SP2 xen Not affected
SUSE Linux Enterprise Software Development Kit 12 SP3 xen Not affected
SUSE Linux Enterprise Software Development Kit 12 SP4 xen Not affected
SUSE Linux Enterprise Software Development Kit 12 SP5 xen Not affected
SUSE Manager Proxy 4.0 xen Not affected
SUSE Manager Proxy 4.1 xen Not affected
SUSE Manager Proxy 4.2 xen Not affected
SUSE Manager Retail Branch Server 4.0 xen Not affected
SUSE Manager Retail Branch Server 4.1 xen Not affected
SUSE Manager Retail Branch Server 4.2 xen Not affected
SUSE Manager Server 4.0 xen Not affected
SUSE Manager Server 4.1 xen Not affected
SUSE Manager Server 4.2 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
openSUSE Leap 15.3 xen Not affected
openSUSE Leap Micro 5.2 xen Not affected


SUSE Timeline for this CVE

CVE page created: Wed Dec 2 10:48:06 2020
CVE page last modified: Thu Nov 14 17:27:12 2024