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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities
NOTICE UPDATE

NIST has updated the NVD program announcement page with additional information regarding recent concerns and the temporary delays in enrichment efforts.

CVE-2021-29657 Detail

Description

arch/x86/kvm/svm/nested.c in the Linux kernel before 5.11.12 has a use-after-free in which an AMD KVM guest can bypass access control on host OS MSRs when there are nested guests, aka CID-a58d9166a756. This occurs because of a TOCTOU race condition associated with a VMCB12 double fetch in nested_svm_vmrun.


Severity

 


CVSS 3.x Severity and Metrics:

NIST CVSS score
NIST: NVD
Base Score:  7.4 HIGH
Vector:  CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: NVD Analysts have published a CVSS score for this CVE based on publicly available information at the time of analysis. The CNA has not provided a score within the CVE List.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html Third Party Advisory  VDB Entry 
https://bugs.chromium.org/p/project-zero/issues/detail?id=2177 Exploit  Mailing List  Patch  Third Party Advisory 
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12 Exploit  Patch  Vendor Advisory 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134 Patch  Third Party Advisory 
https://security.netapp.com/advisory/ntap-20210902-0008/ Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition cwe source acceptance level NIST  
CWE-416 Use After Free cwe source acceptance level NIST  

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-2021-29657
NVD Published Date:
07/22/2021
NVD Last Modified:
05/19/2023
Source:
MITRE