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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2021-3656 Detail

Description

A 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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://bugzilla.redhat.com/show_bug.cgi?id=1983988 Issue Tracking  Third Party Advisory 
https://bugzilla.redhat.com/show_bug.cgi?id=1983988 Issue Tracking  Third Party Advisory 
https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc Patch  Third Party Advisory 
https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc Patch  Third Party Advisory 
https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc Patch  Third Party Advisory 
https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc Patch  Third Party Advisory 
https://www.openwall.com/lists/oss-security/2021/08/16/1 Mailing List  Third Party Advisory 
https://www.openwall.com/lists/oss-security/2021/08/16/1 Mailing List  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-862 Missing Authorization cwe source acceptance level NIST   Red Hat, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-3656
NVD Published Date:
03/04/2022
NVD Last Modified:
11/21/2024
Source:
Red Hat, Inc.