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GSD-2021-29657

Vulnerability from gsd - Updated: 2023-12-13 01:23
Details
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.
Aliases
Aliases

{
  "GSD": {
    "alias": "CVE-2021-29657",
    "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.",
    "id": "GSD-2021-29657",
    "references": [
      "https://www.suse.com/security/cve/CVE-2021-29657.html",
      "https://ubuntu.com/security/CVE-2021-29657",
      "https://advisories.mageia.org/CVE-2021-29657.html",
      "https://security.archlinux.org/CVE-2021-29657",
      "https://packetstormsecurity.com/files/cve/CVE-2021-29657"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-29657"
      ],
      "details": "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.",
      "id": "GSD-2021-29657",
      "modified": "2023-12-13T01:23:36.359923Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
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        "ASSIGNER": "cve@mitre.org",
        "ID": "CVE-2021-29657",
        "STATE": "PUBLIC"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
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              "product": {
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                  {
                    "product_name": "n/a",
                    "version": {
                      "version_data": [
                        {
                          "version_value": "n/a"
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          }
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      "references": {
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          {
            "name": "http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html",
            "refsource": "MISC",
            "url": "http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html"
          },
          {
            "name": "https://bugs.chromium.org/p/project-zero/issues/detail?id=2177",
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          },
          {
            "name": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134",
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          },
          {
            "name": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12",
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            "url": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12"
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          }
        ]
      }
    },
    "nvd.nist.gov": {
      "configurations": {
        "CVE_data_version": "4.0",
        "nodes": [
          {
            "children": [],
            "cpe_match": [
              {
                "cpe23Uri": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "cpe_name": [],
                "versionEndExcluding": "5.10.28",
                "versionStartIncluding": "5.10",
                "vulnerable": true
              },
              {
                "cpe23Uri": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "cpe_name": [],
                "versionEndExcluding": "5.11.12",
                "versionStartIncluding": "5.11",
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              }
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        "description": {
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              "value": "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."
            }
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        "problemtype": {
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                {
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              "name": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134",
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              "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134"
            },
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            },
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              "refsource": "MISC",
              "tags": [
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              "url": "http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html"
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      },
      "impact": {
        "baseMetricV2": {
          "acInsufInfo": false,
          "cvssV2": {
            "accessComplexity": "MEDIUM",
            "accessVector": "LOCAL",
            "authentication": "NONE",
            "availabilityImpact": "COMPLETE",
            "baseScore": 6.9,
            "confidentialityImpact": "COMPLETE",
            "integrityImpact": "COMPLETE",
            "vectorString": "AV:L/AC:M/Au:N/C:C/I:C/A:C",
            "version": "2.0"
          },
          "exploitabilityScore": 3.4,
          "impactScore": 10.0,
          "obtainAllPrivilege": false,
          "obtainOtherPrivilege": false,
          "obtainUserPrivilege": false,
          "severity": "MEDIUM",
          "userInteractionRequired": false
        },
        "baseMetricV3": {
          "cvssV3": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 1.4,
          "impactScore": 5.9
        }
      },
      "lastModifiedDate": "2023-05-19T16:51Z",
      "publishedDate": "2021-07-22T17:15Z"
    }
  }
}



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