CVE-2021-3656

Summary

CVECVE-2021-3656
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2022-03-04 19:15:00 UTC
Updated2023-01-19 15:53:00 UTC
DescriptionA flaw was found in the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "virt_ext" field, this issue could allow a malicious L1 to disable both VMLOAD/VMSAVE intercepts and VLS (Virtual VMLOAD/VMSAVE) for the L2 guest. As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape.

Risk And Classification

Problem Types: CWE-862

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Fedoraproject Fedora 33 All All All
Operating System Fedoraproject Fedora 34 All All All
Operating System Linux Linux Kernel All All All All
Operating System Linux Linux Kernel 5.14 - All All
Operating System Linux Linux Kernel 5.14 rc1 All All
Operating System Linux Linux Kernel 5.14 rc2 All All
Operating System Linux Linux Kernel 5.14 rc3 All All
Operating System Linux Linux Kernel 5.14 rc4 All All
Operating System Linux Linux Kernel 5.14 rc5 All All
Operating System Linux Linux Kernel 5.14 rc6 All All
Application Redhat 3scale Api Management 2.0 All All All
Application Redhat Codeready Linux Builder - All All All
Operating System Redhat Enterprise Linux 7.0 All All All
Operating System Redhat Enterprise Linux 8.0 All All All
Operating System Redhat Enterprise Linux 8.0 All All All
Operating System Redhat Enterprise Linux Desktop 7.0 All All All
Operating System Redhat Enterprise Linux Eus 8.1 All All All
Operating System Redhat Enterprise Linux Eus 8.2 All All All
Operating System Redhat Enterprise Linux Eus 8.4 All All All
Operating System Redhat Enterprise Linux Eus 8.1 All All All
Operating System Redhat Enterprise Linux Eus 8.2 All All All
Operating System Redhat Enterprise Linux Eus 8.4 All All All
Operating System Redhat Enterprise Linux For Ibm Z Systems 7.0 All All All
Operating System Redhat Enterprise Linux For Ibm Z Systems 8.0 All All All
Operating System Redhat Enterprise Linux For Ibm Z Systems Eus 8.1 All All All
Operating System Redhat Enterprise Linux For Ibm Z Systems Eus 8.2 All All All
Operating System Redhat Enterprise Linux For Ibm Z Systems Eus 8.4 All All All
Operating System Redhat Enterprise Linux For Power Big Endian 7.0 All All All
Operating System Redhat Enterprise Linux For Power Little Endian 8.0 All All All
Operating System Redhat Enterprise Linux For Power Little Endian 7.0 All All All
Operating System Redhat Enterprise Linux For Power Little Endian 8.0 All All All
Operating System Redhat Enterprise Linux For Power Little Endian Eus 8.1 All All All
Operating System Redhat Enterprise Linux For Power Little Endian Eus 8.2 All All All
Operating System Redhat Enterprise Linux For Power Little Endian Eus 8.4 All All All
Operating System Redhat Enterprise Linux For Power Little Endian Eus 8.1 All All All
Operating System Redhat Enterprise Linux For Power Little Endian Eus 8.2 All All All
Operating System Redhat Enterprise Linux For Power Little Endian Eus 8.4 All All All
Operating System Redhat Enterprise Linux For Real Time 7 All All All
Operating System Redhat Enterprise Linux For Real Time 8 All All All
Operating System Redhat Enterprise Linux For Real Time For Nfv 7 All All All
Operating System Redhat Enterprise Linux For Real Time For Nfv 8 All All All
Operating System Redhat Enterprise Linux For Real Time For Nfv Tus 8.2 All All All
Operating System Redhat Enterprise Linux For Real Time For Nfv Tus 8.4 All All All
Operating System Redhat Enterprise Linux For Real Time Tus 8.2 All All All
Operating System Redhat Enterprise Linux For Real Time Tus 8.4 All All All
Operating System Redhat Enterprise Linux For Scientific Computing 7.0 All All All
Operating System Redhat Enterprise Linux Server 7.0 All All All
Operating System Redhat Enterprise Linux Server 7.0 All All All
Operating System Redhat Enterprise Linux Server Aus 7.6 All All All
Operating System Redhat Enterprise Linux Server Aus 7.7 All All All
Operating System Redhat Enterprise Linux Server Aus 8.2 All All All
Operating System Redhat Enterprise Linux Server Aus 8.4 All All All
Operating System Redhat Enterprise Linux Server For Power Little Endian Update Services For Sap Solutions 7.6 All All All
Operating System Redhat Enterprise Linux Server For Power Little Endian Update Services For Sap Solutions 8.1 All All All
Operating System Redhat Enterprise Linux Server For Power Little Endian Update Services For Sap Solutions 8.2 All All All
Operating System Redhat Enterprise Linux Server For Power Little Endian Update Services For Sap Solutions 8.4 All All All
Operating System Redhat Enterprise Linux Server Tus 7.6 All All All
Operating System Redhat Enterprise Linux Server Tus 7.7 All All All
Operating System Redhat Enterprise Linux Server Tus 8.2 All All All
Operating System Redhat Enterprise Linux Server Tus 8.4 All All All
Operating System Redhat Enterprise Linux Server Update Services For Sap Solutions 7.6 All All All
Operating System Redhat Enterprise Linux Server Update Services For Sap Solutions 7.7 All All All
Operating System Redhat Enterprise Linux Server Update Services For Sap Solutions 8.1 All All All
Operating System Redhat Enterprise Linux Server Update Services For Sap Solutions 8.2 All All All
Operating System Redhat Enterprise Linux Server Update Services For Sap Solutions 8.4 All All All
Operating System Redhat Enterprise Linux Workstation 7.0 All All All
Application Redhat Openstack 13 All All All
Application Redhat Software Collections - All All All
Application Redhat Virtualization Host 4.0 All All All

References

ReferenceSourceLinkTags
1983988 – (CVE-2021-3656) CVE-2021-3656 kernel: SVM nested virtualization issue in KVM (VMLOAD/VMSAVE) MISC bugzilla.redhat.com
oss-security - [CVE-2021-3653, CVE-2021-3656] SVM nested virtualization issues in KVM MISC www.openwall.com
KVM: nSVM: always intercept VMLOAD/VMSAVE when nested (CVE-2021-3656) · torvalds/linux@c7dfa40 · GitHub MISC github.com
kvm/kvm.git - kernel-based virtual machine - kvm MISC git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 159364 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2021-9419)
  • 159365 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2021-9420)
  • 159366 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel-container (ELSA-2021-9421)
  • 159367 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel-container (ELSA-2021-9422)
  • 159393 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2021-9450)
  • 159394 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel-container (ELSA-2021-9451)
  • 159399 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2021-9452)
  • 159400 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel-container (ELSA-2021-9453)
  • 159415 Oracle Enterprise Linux Security Update for kernel (ELSA-2021-3801)
  • 159443 Oracle Enterprise Linux Security Update for kernel (ELSA-2021-4056)
  • 159564 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2021-9564)
  • 159565 Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel-container (ELSA-2021-9565)
  • 159727 Oracle Enterprise Linux Security Update for unbreakable enterprise kernel-container (ELSA-2022-9245)
  • 159729 Oracle Enterprise Linux Security Update for unbreakable enterprise kernel (ELSA-2022-9244)
  • 178809 Debian Security Update for linux (DSA 4978-1)
  • 178844 Debian Security Update for linux-4.19 (DLA 2785-1)
  • 180048 Debian Security Update for linux (CVE-2021-3656)
  • 198487 Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-5071-1)
  • 198491 Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-5070-1)
  • 198495 Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-5072-1)
  • 198497 Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-5073-1)
  • 198502 Ubuntu Security Notification for Linux kernel (HWE) Vulnerabilities (USN-5071-2)
  • 198504 Ubuntu Security Notification for Linux kernel (OEM) Vulnerabilities (USN-5082-1)
  • 198506 Ubuntu Security Notification for Linux kernel (GCP) Vulnerabilities (USN-5073-2)
  • 239656 Red Hat Update for kernel (RHSA-2021:3676)
  • 239675 Red Hat Update for kernel-rt (RHSA-2021:3802)
  • 239676 Red Hat Update for kernel (RHSA-2021:3801)
  • 239689 Red Hat Update for kernel-rt (RHSA-2021:3909)
  • 239691 Red Hat Update for kernel (RHSA-2021:3904)
  • 239762 Red Hat Update for kernel-rt (RHSA-2021:4088)
  • 239771 Red Hat Update for kernel security (RHSA-2021:4056)
  • 257119 CentOS Security Update for kernel (CESA-2021:3801)
  • 281837 Fedora Security Update for kernel (FEDORA-2021-a424256622)
  • 281838 Fedora Security Update for kernel (FEDORA-2021-33819e6b09)
  • 352839 Amazon Linux Security Advisory for kernel: ALAS2-2021-1704
  • 353155 Amazon Linux Security Advisory for kernel : ALAS2KERNEL-5.10-2022-005
  • 356186 Amazon Linux Security Advisory for microvm-kernel : ALASMICROVM-KERNEL-4.14-2023-003
  • 356218 Amazon Linux Security Advisory for microvm-kernel : ALASMICROVM-KERNEL-4.14-2023-002
  • 6140281 AWS Bottlerocket Security Update for kernel (GHSA-9gv2-fc96-xqcj)
  • 671137 EulerOS Security Update for kernel (EulerOS-SA-2021-2713)
  • 751137 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:1271-1)
  • 751155 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:3192-1)
  • 751160 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:3179-1)
  • 751163 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:3206-1)
  • 751170 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:3205-1)
  • 751437 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:3876-1)
  • 751441 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:3876-1)
  • 751473 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:3969-1)
  • 751476 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:3972-1)
  • 900729 Common Base Linux Mariner (CBL-Mariner) Security Update for kernel (8878)
  • 905818 Common Base Linux Mariner (CBL-Mariner) Security Update for kernel (8878-1)
  • 940068 AlmaLinux Security Update for kernel (ALSA-2021:4056)
  • 960019 Rocky Linux Security Update for kernel-rt (RLSA-2021:4088)
  • 960061 Rocky Linux Security Update for kernel (RLSA-2021:4056)
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