Upstream information

CVE-2020-25598 at MITRE

Description

An issue was discovered in Xen 4.14.x. There is a missing unlock in the XENMEM_acquire_resource error path. The RCU (Read, Copy, Update) mechanism is a synchronisation primitive. A buggy error path in the XENMEM_acquire_resource exits without releasing an RCU reference, which is conceptually similar to forgetting to unlock a spinlock. A buggy or malicious HVM stubdomain can cause an RCU reference to be leaked. This causes subsequent administration operations, (e.g., CPU offline) to livelock, resulting in a host Denial of Service. The buggy codepath has been present since Xen 4.12. Xen 4.14 and later are vulnerable to the DoS. The side effects are believed to be benign on Xen 4.12 and 4.13, but patches are provided nevertheless. The vulnerability can generally only be exploited by x86 HVM VMs, as these are generally the only type of VM that have a Qemu stubdomain. x86 PV and PVH domains, as well as ARM VMs, typically don't use a stubdomain. Only VMs using HVM stubdomains can exploit the vulnerability. VMs using PV stubdomains, or with emulators running in dom0, cannot exploit the vulnerability.

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 2.1
Vector AV:L/AC:L/Au:N/C:N/I:N/A:P
Access Vector Local
Access Complexity Low
Authentication None
Confidentiality Impact None
Integrity Impact None
Availability Impact Partial
CVSS v3 Scores
  National Vulnerability Database SUSE
Base Score 5.5 6.5
Vector CVSS:3.1/AV:L/AC:L/PR:L/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 Low 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: 1176341 [NEW]

SUSE Security Advisories:

List of released packages

Product(s) Fixed package version(s) References
Image SLES15-SP1-CHOST-BYOS-EC2
  • xen-libs >= 4.12.3_08-3.28.1
  • xen-tools-domU >= 4.12.3_08-3.28.1
Image SLES15-SP2-CHOST-BYOS-Ali
Image SLES15-SP2-CHOST-BYOS-Azure
Image SLES15-SP2-CHOST-BYOS-GCE
Image SLES15-SP2-CHOST-BYOS-OpenStack
  • xen-libs >= 4.13.1_08-3.10.1
Image SLES15-SP2-CHOST-BYOS-EC2
  • xen-libs >= 4.13.1_08-3.10.1
  • xen-tools-domU >= 4.13.1_08-3.10.1
SUSE Linux Enterprise Module for Basesystem 15 SP1
  • xen >= 4.12.3_08-3.28.1
  • xen-libs >= 4.12.3_08-3.28.1
  • xen-tools-domU >= 4.12.3_08-3.28.1
Patchnames:
SUSE-SLE-Module-Basesystem-15-SP1-2020-2790
SUSE Linux Enterprise Module for Basesystem 15 SP2
  • xen >= 4.13.1_08-3.10.1
  • xen-libs >= 4.13.1_08-3.10.1
  • xen-tools-domU >= 4.13.1_08-3.10.1
Patchnames:
SUSE-SLE-Module-Basesystem-15-SP2-2020-2791
SUSE Linux Enterprise Module for Open Buildservice Development Tools 15 SP1
  • xen >= 4.12.3_08-3.28.1
  • xen-devel >= 4.12.3_08-3.28.1
  • xen-doc-html >= 4.12.3_08-3.28.1
  • xen-libs >= 4.12.3_08-3.28.1
  • xen-libs-32bit >= 4.12.3_08-3.28.1
  • xen-tools >= 4.12.3_08-3.28.1
  • xen-tools-domU >= 4.12.3_08-3.28.1
Patchnames:
SUSE-SLE-Module-Development-Tools-OBS-15-SP1-2020-2790
SUSE Linux Enterprise Module for Open Buildservice Development Tools 15 SP2
  • xen >= 4.13.1_08-3.10.1
  • xen-devel >= 4.13.1_08-3.10.1
  • xen-doc-html >= 4.13.1_08-3.10.1
  • xen-libs >= 4.13.1_08-3.10.1
  • xen-libs-32bit >= 4.13.1_08-3.10.1
  • xen-tools >= 4.13.1_08-3.10.1
  • xen-tools-domU >= 4.13.1_08-3.10.1
Patchnames:
SUSE-SLE-Module-Development-Tools-OBS-15-SP2-2020-2791
SUSE Linux Enterprise Module for Server Applications 15 SP1
  • xen >= 4.12.3_08-3.28.1
  • xen-devel >= 4.12.3_08-3.28.1
  • xen-tools >= 4.12.3_08-3.28.1
Patchnames:
SUSE-SLE-Module-Server-Applications-15-SP1-2020-2790
SUSE Linux Enterprise Module for Server Applications 15 SP2
  • xen >= 4.13.1_08-3.10.1
  • xen-devel >= 4.13.1_08-3.10.1
  • xen-tools >= 4.13.1_08-3.10.1
  • xen-tools-xendomains-wait-disk >= 4.13.1_08-3.10.1
Patchnames:
SUSE-SLE-Module-Server-Applications-15-SP2-2020-2791
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server for SAP Applications 12 SP5
  • xen >= 4.12.3_08-3.24.1
  • xen-doc-html >= 4.12.3_08-3.24.1
  • xen-libs >= 4.12.3_08-3.24.1
  • xen-libs-32bit >= 4.12.3_08-3.24.1
  • xen-tools >= 4.12.3_08-3.24.1
  • xen-tools-domU >= 4.12.3_08-3.24.1
Patchnames:
SUSE-SLE-SERVER-12-SP5-2020-2788
SUSE Linux Enterprise Software Development Kit 12 SP5
  • xen >= 4.12.3_08-3.24.1
  • xen-devel >= 4.12.3_08-3.24.1
Patchnames:
SUSE-SLE-SDK-12-SP5-2020-2788
openSUSE Leap 15.2
  • xen >= 4.13.1_08-lp152.2.9.1
  • xen-debugsource >= 4.13.1_08-lp152.2.9.1
  • xen-devel >= 4.13.1_08-lp152.2.9.1
  • xen-doc-html >= 4.13.1_08-lp152.2.9.1
  • xen-libs >= 4.13.1_08-lp152.2.9.1
  • xen-libs-32bit >= 4.13.1_08-lp152.2.9.1
  • xen-libs-32bit-debuginfo >= 4.13.1_08-lp152.2.9.1
  • xen-libs-debuginfo >= 4.13.1_08-lp152.2.9.1
  • xen-tools >= 4.13.1_08-lp152.2.9.1
  • xen-tools-debuginfo >= 4.13.1_08-lp152.2.9.1
  • xen-tools-domU >= 4.13.1_08-lp152.2.9.1
  • xen-tools-domU-debuginfo >= 4.13.1_08-lp152.2.9.1
  • xen-tools-xendomains-wait-disk >= 4.13.1_08-lp152.2.9.1
Patchnames:
openSUSE-2020-1608


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
SUSE CaaS Platform 3.0 xen Not affected
SUSE Container as a Service Platform 1.0 xen Not affected
SUSE Container as a Service Platform 2.0 xen Not affected
SUSE Linux Enterprise 15-SP1 Module for Basesystem xen Released
SUSE Linux Enterprise 15-SP1 Module for Server Applications xen Released
SUSE Linux Enterprise 15-SP2 Module for Basesystem xen Released
SUSE Linux Enterprise 15-SP2 Module for Server Applications xen Released
SUSE Linux Enterprise High Performance Computing 12 SP4 xen Not affected
SUSE Linux Enterprise High Performance Computing 12 SP5 xen Released
SUSE Linux Enterprise High Performance Computing 15 LTSS xen Not affected
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 LTSS xen Not affected
SUSE Linux Enterprise Server 12 SP3 BCL xen Not affected
SUSE Linux Enterprise Server 12 SP3 LTSS xen Not affected
SUSE Linux Enterprise Server 12 SP4 LTSS xen Not affected
SUSE Linux Enterprise Server 12 SP5 xen Released
SUSE Linux Enterprise Server ESPOS 15 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 12 SP5 xen Released
SUSE Linux Enterprise Software Development Kit 12 SP5 xen Affected