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 ?
No CVSS data available.
CWE
  • n/a
Assigner
References
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T22:11:06.370Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://bugs.chromium.org/p/project-zero/issues/detail?id=2177"
          },
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134"
          },
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12"
          },
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://security.netapp.com/advisory/ntap-20210902-0008/"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "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."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "n/a",
              "lang": "en",
              "type": "text"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2021-09-02T08:06:31.000Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://bugs.chromium.org/p/project-zero/issues/detail?id=2177"
        },
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134"
        },
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12"
        },
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://security.netapp.com/advisory/ntap-20210902-0008/"
        }
      ],
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "cve@mitre.org",
          "ID": "CVE-2021-29657",
          "STATE": "PUBLIC"
        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "n/a",
                      "version": {
                        "version_data": [
                          {
                            "version_value": "n/a"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "n/a"
              }
            ]
          }
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "eng",
              "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."
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "eng",
                  "value": "n/a"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "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",
              "refsource": "MISC",
              "url": "https://bugs.chromium.org/p/project-zero/issues/detail?id=2177"
            },
            {
              "name": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134",
              "refsource": "CONFIRM",
              "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134"
            },
            {
              "name": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12",
              "refsource": "CONFIRM",
              "url": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12"
            },
            {
              "name": "https://security.netapp.com/advisory/ntap-20210902-0008/",
              "refsource": "CONFIRM",
              "url": "https://security.netapp.com/advisory/ntap-20210902-0008/"
            }
          ]
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2021-29657",
    "datePublished": "2021-07-22T16:44:33.000Z",
    "dateReserved": "2021-03-31T00:00:00.000Z",
    "dateUpdated": "2024-08-03T22:11:06.370Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2021-29657",
      "date": "2026-05-14",
      "epss": "0.00047",
      "percentile": "0.14588"
    },
    "fkie_nvd": {
      "configurations": "[{\"nodes\": [{\"operator\": \"OR\", \"negate\": false, \"cpeMatch\": [{\"vulnerable\": true, \"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"versionStartIncluding\": \"5.10\", \"versionEndExcluding\": \"5.10.28\", \"matchCriteriaId\": \"EC50161C-1BB2-406D-8DA1-1A7F5F473581\"}, {\"vulnerable\": true, \"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"versionStartIncluding\": \"5.11\", \"versionEndExcluding\": \"5.11.12\", \"matchCriteriaId\": \"4D2300F5-4A31-4893-A7E9-F2B13748BF38\"}]}]}]",
      "descriptions": "[{\"lang\": \"en\", \"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.\"}, {\"lang\": \"es\", \"value\": \"El archivo arch/x86/kvm/svm/nested.c en el kernel de Linux versiones anteriores a 5.11.12, presenta un uso de memoria previamente liberada en el que un invitado KVM de AMD puede omitir el control de acceso en los MSR del SO anfitri\\u00f3n cuando se presentan invitados anidados, tambi\\u00e9n se conoce como CID-a58d9166a756. Esto ocurre debido a una condici\\u00f3n de carrera TOCTOU asociada con un doble fetch VMCB12 en la funci\\u00f3n nested_svm_vmrun\"}]",
      "id": "CVE-2021-29657",
      "lastModified": "2024-11-21T06:01:35.567",
      "metrics": "{\"cvssMetricV31\": [{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"3.1\", \"vectorString\": \"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H\", \"baseScore\": 7.4, \"baseSeverity\": \"HIGH\", \"attackVector\": \"LOCAL\", \"attackComplexity\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"userInteraction\": \"NONE\", \"scope\": \"UNCHANGED\", \"confidentialityImpact\": \"HIGH\", \"integrityImpact\": \"HIGH\", \"availabilityImpact\": \"HIGH\"}, \"exploitabilityScore\": 1.4, \"impactScore\": 5.9}], \"cvssMetricV2\": [{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"2.0\", \"vectorString\": \"AV:L/AC:M/Au:N/C:C/I:C/A:C\", \"baseScore\": 6.9, \"accessVector\": \"LOCAL\", \"accessComplexity\": \"MEDIUM\", \"authentication\": \"NONE\", \"confidentialityImpact\": \"COMPLETE\", \"integrityImpact\": \"COMPLETE\", \"availabilityImpact\": \"COMPLETE\"}, \"baseSeverity\": \"MEDIUM\", \"exploitabilityScore\": 3.4, \"impactScore\": 10.0, \"acInsufInfo\": false, \"obtainAllPrivilege\": false, \"obtainUserPrivilege\": false, \"obtainOtherPrivilege\": false, \"userInteractionRequired\": false}]}",
      "published": "2021-07-22T17:15:09.470",
      "references": "[{\"url\": \"http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html\", \"source\": \"cve@mitre.org\", \"tags\": [\"Third Party Advisory\", \"VDB Entry\"]}, {\"url\": \"https://bugs.chromium.org/p/project-zero/issues/detail?id=2177\", \"source\": \"cve@mitre.org\", \"tags\": [\"Exploit\", \"Mailing List\", \"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12\", \"source\": \"cve@mitre.org\", \"tags\": [\"Exploit\", \"Patch\", \"Vendor Advisory\"]}, {\"url\": \"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134\", \"source\": \"cve@mitre.org\", \"tags\": [\"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://security.netapp.com/advisory/ntap-20210902-0008/\", \"source\": \"cve@mitre.org\", \"tags\": [\"Third Party Advisory\"]}, {\"url\": \"http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Third Party Advisory\", \"VDB Entry\"]}, {\"url\": \"https://bugs.chromium.org/p/project-zero/issues/detail?id=2177\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Exploit\", \"Mailing List\", \"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Exploit\", \"Patch\", \"Vendor Advisory\"]}, {\"url\": \"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://security.netapp.com/advisory/ntap-20210902-0008/\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Third Party Advisory\"]}]",
      "sourceIdentifier": "cve@mitre.org",
      "vulnStatus": "Modified",
      "weaknesses": "[{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"description\": [{\"lang\": \"en\", \"value\": \"CWE-367\"}, {\"lang\": \"en\", \"value\": \"CWE-416\"}]}]"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2021-29657\",\"sourceIdentifier\":\"cve@mitre.org\",\"published\":\"2021-07-22T17:15:09.470\",\"lastModified\":\"2024-11-21T06:01:35.567\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"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.\"},{\"lang\":\"es\",\"value\":\"El archivo arch/x86/kvm/svm/nested.c en el kernel de Linux versiones anteriores a 5.11.12, presenta un uso de memoria previamente liberada en el que un invitado KVM de AMD puede omitir el control de acceso en los MSR del SO anfitri\u00f3n cuando se presentan invitados anidados, tambi\u00e9n se conoce como CID-a58d9166a756. Esto ocurre debido a una condici\u00f3n de carrera TOCTOU asociada con un doble fetch VMCB12 en la funci\u00f3n nested_svm_vmrun\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.4,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.4,\"impactScore\":5.9}],\"cvssMetricV2\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"2.0\",\"vectorString\":\"AV:L/AC:M/Au:N/C:C/I:C/A:C\",\"baseScore\":6.9,\"accessVector\":\"LOCAL\",\"accessComplexity\":\"MEDIUM\",\"authentication\":\"NONE\",\"confidentialityImpact\":\"COMPLETE\",\"integrityImpact\":\"COMPLETE\",\"availabilityImpact\":\"COMPLETE\"},\"baseSeverity\":\"MEDIUM\",\"exploitabilityScore\":3.4,\"impactScore\":10.0,\"acInsufInfo\":false,\"obtainAllPrivilege\":false,\"obtainUserPrivilege\":false,\"obtainOtherPrivilege\":false,\"userInteractionRequired\":false}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-367\"},{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.10\",\"versionEndExcluding\":\"5.10.28\",\"matchCriteriaId\":\"EC50161C-1BB2-406D-8DA1-1A7F5F473581\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.11\",\"versionEndExcluding\":\"5.11.12\",\"matchCriteriaId\":\"4D2300F5-4A31-4893-A7E9-F2B13748BF38\"}]}]}],\"references\":[{\"url\":\"http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html\",\"source\":\"cve@mitre.org\",\"tags\":[\"Third Party Advisory\",\"VDB Entry\"]},{\"url\":\"https://bugs.chromium.org/p/project-zero/issues/detail?id=2177\",\"source\":\"cve@mitre.org\",\"tags\":[\"Exploit\",\"Mailing List\",\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12\",\"source\":\"cve@mitre.org\",\"tags\":[\"Exploit\",\"Patch\",\"Vendor Advisory\"]},{\"url\":\"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134\",\"source\":\"cve@mitre.org\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://security.netapp.com/advisory/ntap-20210902-0008/\",\"source\":\"cve@mitre.org\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Third Party Advisory\",\"VDB Entry\"]},{\"url\":\"https://bugs.chromium.org/p/project-zero/issues/detail?id=2177\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Exploit\",\"Mailing List\",\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Exploit\",\"Patch\",\"Vendor Advisory\"]},{\"url\":\"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://security.netapp.com/advisory/ntap-20210902-0008/\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Third Party Advisory\"]}]}}"
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.