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CVE-2021-29657 (GCVE-0-2021-29657)

Vulnerability from cvelistv5 – Published: 2021-07-22 16:44 – Updated: 2024-08-03 22:11
VLAI
Summary
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
7.4 (High)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • n/a
Assigner
References
Show details on NVD website
To clipboard 

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      "current_release_date": "2026-06-28T12:05:37+00:00",
      "cve": "CVE-2021-29657",
      "id": "CVE-2021-29657",
      "initial_release_date": "2021-03-31T00:00:00+00:00",
      "product_status:fixed": "120",
      "product_status:known_affected": "16",
      "product_status:known_not_affected": "149",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: KVM: double fetch in nested_svm_vmrun can lead to unrestricted MSR access",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-29657.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-07-28T23:55:05Z",
      "cve": "CVE-2021-29657",
      "id": "CVE-2021-29657",
      "initial_release_date": "2023-02-15T03:42:46Z",
      "product_status:known_not_affected": "320",
      "product_status:recommended": "20",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2021-29657",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-29657.json",
      "version": "15"
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  }
}



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