GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2021-47217 (GCVE-0-2021-47217)

Vulnerability from cvelistv5 – Published: 2024-04-10 19:01 – Updated: 2026-05-11 13:50
VLAI
Title
x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails
Summary
In the Linux kernel, the following vulnerability has been resolved: x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails Check for a valid hv_vp_index array prior to derefencing hv_vp_index when setting Hyper-V's TSC change callback. If Hyper-V setup failed in hyperv_init(), the kernel will still report that it's running under Hyper-V, but will have silently disabled nearly all functionality. BUG: kernel NULL pointer dereference, address: 0000000000000010 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:set_hv_tscchange_cb+0x15/0xa0 Code: <8b> 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08 ... Call Trace: kvm_arch_init+0x17c/0x280 kvm_init+0x31/0x330 vmx_init+0xba/0x13a do_one_initcall+0x41/0x1c0 kernel_init_freeable+0x1f2/0x23b kernel_init+0x16/0x120 ret_from_fork+0x22/0x30
Severity
No CVSS data available.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-06-17 18:03 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 93286261de1b46339aa27cd4c639b21778f6cade , < b20ec58f8a6f4fef32cc71480ddf824584e24743 (git)
Affected: 93286261de1b46339aa27cd4c639b21778f6cade , < b0e44dfb4e4c699cca33ede431b8d127e6e8d661 (git)
Affected: 93286261de1b46339aa27cd4c639b21778f6cade , < 9c177eee116cf888276d3748cb176e72562cfd5c (git)
Affected: 93286261de1b46339aa27cd4c639b21778f6cade , < 8823ea27fff6084bbb4bc71d15378fae0220b1d8 (git)
Affected: 93286261de1b46339aa27cd4c639b21778f6cade , < daf972118c517b91f74ff1731417feb4270625a4 (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.16
Unaffected: 0 , < 4.16 (semver)
Unaffected: 4.19.218 , ≤ 4.19.* (semver)
Unaffected: 5.4.162 , ≤ 5.4.* (semver)
Unaffected: 5.10.82 , ≤ 5.10.* (semver)
Unaffected: 5.15.5 , ≤ 5.15.* (semver)
Unaffected: 5.16 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47217",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-06-17T18:03:45.646426Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-06-17T18:04:39.738Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T05:32:07.432Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/hyperv/hv_init.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "b20ec58f8a6f4fef32cc71480ddf824584e24743",
              "status": "affected",
              "version": "93286261de1b46339aa27cd4c639b21778f6cade",
              "versionType": "git"
            },
            {
              "lessThan": "b0e44dfb4e4c699cca33ede431b8d127e6e8d661",
              "status": "affected",
              "version": "93286261de1b46339aa27cd4c639b21778f6cade",
              "versionType": "git"
            },
            {
              "lessThan": "9c177eee116cf888276d3748cb176e72562cfd5c",
              "status": "affected",
              "version": "93286261de1b46339aa27cd4c639b21778f6cade",
              "versionType": "git"
            },
            {
              "lessThan": "8823ea27fff6084bbb4bc71d15378fae0220b1d8",
              "status": "affected",
              "version": "93286261de1b46339aa27cd4c639b21778f6cade",
              "versionType": "git"
            },
            {
              "lessThan": "daf972118c517b91f74ff1731417feb4270625a4",
              "status": "affected",
              "version": "93286261de1b46339aa27cd4c639b21778f6cade",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/hyperv/hv_init.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.16"
            },
            {
              "lessThan": "4.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.19.*",
              "status": "unaffected",
              "version": "4.19.218",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.162",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.82",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.16",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.19.218",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.4.162",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.82",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.5",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.16",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails\n\nCheck for a valid hv_vp_index array prior to derefencing hv_vp_index when\nsetting Hyper-V\u0027s TSC change callback.  If Hyper-V setup failed in\nhyperv_init(), the kernel will still report that it\u0027s running under\nHyper-V, but will have silently disabled nearly all functionality.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000010\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: 0000 [#1] SMP\n  CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:set_hv_tscchange_cb+0x15/0xa0\n  Code: \u003c8b\u003e 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08\n  ...\n  Call Trace:\n   kvm_arch_init+0x17c/0x280\n   kvm_init+0x31/0x330\n   vmx_init+0xba/0x13a\n   do_one_initcall+0x41/0x1c0\n   kernel_init_freeable+0x1f2/0x23b\n   kernel_init+0x16/0x120\n   ret_from_fork+0x22/0x30"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T13:50:14.845Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
        },
        {
          "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
        },
        {
          "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
        },
        {
          "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
        },
        {
          "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
        }
      ],
      "title": "x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-47217",
    "datePublished": "2024-04-10T19:01:56.419Z",
    "dateReserved": "2024-04-10T18:59:19.528Z",
    "dateUpdated": "2026-05-11T13:50:14.845Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2021-47217",
      "date": "2026-09-18",
      "epss": "0.00235",
      "percentile": "0.14838"
    },
    "fkie_nvd": {
      "configurations": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "matchCriteriaId": "3917EFBF-AD24-48ED-B8B4-4F6BA6A5E0E0",
                  "versionEndExcluding": "4.19.218",
                  "versionStartIncluding": "4.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "matchCriteriaId": "51A152D8-D5CE-47BD-9041-DEE164DCE99D",
                  "versionEndExcluding": "5.4.162",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "matchCriteriaId": "AE501832-500C-4EF1-9489-5C13674F619D",
                  "versionEndExcluding": "5.10.82",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "matchCriteriaId": "2128A085-4C0C-4C1E-9E9C-0DD868E2170F",
                  "versionEndExcluding": "5.15.5",
                  "versionStartIncluding": "5.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*",
                  "matchCriteriaId": "357AA433-37E8-4323-BFB2-3038D6E4B414",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails\n\nCheck for a valid hv_vp_index array prior to derefencing hv_vp_index when\nsetting Hyper-V\u0027s TSC change callback.  If Hyper-V setup failed in\nhyperv_init(), the kernel will still report that it\u0027s running under\nHyper-V, but will have silently disabled nearly all functionality.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000010\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: 0000 [#1] SMP\n  CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:set_hv_tscchange_cb+0x15/0xa0\n  Code: \u003c8b\u003e 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08\n  ...\n  Call Trace:\n   kvm_arch_init+0x17c/0x280\n   kvm_init+0x31/0x330\n   vmx_init+0xba/0x13a\n   do_one_initcall+0x41/0x1c0\n   kernel_init_freeable+0x1f2/0x23b\n   kernel_init+0x16/0x120\n   ret_from_fork+0x22/0x30"
        },
        {
          "lang": "es",
          "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: x86/hyperv: Se corrige la desreferencia NULL en set_hv_tscchange_cb() si falla la configuraci\u00f3n de Hyper-V. Verifique si hay una matriz hv_vp_index v\u00e1lida antes de desreferenciar hv_vp_index al configurar la devoluci\u00f3n de llamada de cambio de TSC de Hyper-V. Si la configuraci\u00f3n de Hyper-V fall\u00f3 en hyperv_init(), el kernel a\u00fan informar\u00e1 que se est\u00e1 ejecutando bajo Hyper-V, pero habr\u00e1 deshabilitado silenciosamente casi todas las funciones. ERROR: desreferencia de puntero NULL del kernel, direcci\u00f3n: 0000000000000010 #PF: acceso de lectura del supervisor en modo kernel #PF: error_code(0x0000) - p\u00e1gina no presente PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 4 PID: 1 Comm: swapper/0 No contaminado 5.15.0-rc2+ #75 Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:set_hv_tscchange_cb+0x15/0xa0 C\u00f3digo: \u0026lt;8b\u0026gt; 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08 ... Seguimiento de llamadas: kvm_arch_init+0x17c/0x280 kvm_init+0x31/0x330 vmx_init+0xba/0x13a do_one_initcall+0x41/0x1c0 kernel_init_freeable+0x1f2/0x23b kernel_init+0x16/0x120 ret_from_fork+0x22/0x30"
        }
      ],
      "id": "CVE-2021-47217",
      "lastModified": "2025-01-14T14:44:11.917",
      "metrics": {
        "cvssMetricV31": [
          {
            "cvssData": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 5.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
              "version": "3.1"
            },
            "exploitabilityScore": 1.8,
            "impactScore": 3.6,
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      },
      "published": "2024-04-10T19:15:48.813",
      "references": [
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
        },
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
        },
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
        },
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
        },
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "tags": [
            "Patch"
          ],
          "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
        }
      ],
      "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "vulnStatus": "Analyzed",
      "weaknesses": [
        {
          "description": [
            {
              "lang": "en",
              "value": "CWE-476"
            }
          ],
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ]
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "arch/x86/hyperv/hv_init.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "b20ec58f8a6f4fef32cc71480ddf824584e24743",
                    "status": "affected",
                    "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "b0e44dfb4e4c699cca33ede431b8d127e6e8d661",
                    "status": "affected",
                    "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "9c177eee116cf888276d3748cb176e72562cfd5c",
                    "status": "affected",
                    "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "8823ea27fff6084bbb4bc71d15378fae0220b1d8",
                    "status": "affected",
                    "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "daf972118c517b91f74ff1731417feb4270625a4",
                    "status": "affected",
                    "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "arch/x86/hyperv/hv_init.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "4.16"
                  },
                  {
                    "lessThan": "4.16",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "4.19.*",
                    "status": "unaffected",
                    "version": "4.19.218",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.4.*",
                    "status": "unaffected",
                    "version": "5.4.162",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.82",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.5",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "5.16",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "3917EFBF-AD24-48ED-B8B4-4F6BA6A5E0E0",
                    "versionEndExcluding": "4.19.218",
                    "versionStartIncluding": "4.16",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "51A152D8-D5CE-47BD-9041-DEE164DCE99D",
                    "versionEndExcluding": "5.4.162",
                    "versionStartIncluding": "4.20",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "AE501832-500C-4EF1-9489-5C13674F619D",
                    "versionEndExcluding": "5.10.82",
                    "versionStartIncluding": "5.5",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "2128A085-4C0C-4C1E-9E9C-0DD868E2170F",
                    "versionEndExcluding": "5.15.5",
                    "versionStartIncluding": "5.11",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "357AA433-37E8-4323-BFB2-3038D6E4B414",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails\n\nCheck for a valid hv_vp_index array prior to derefencing hv_vp_index when\nsetting Hyper-V\u0027s TSC change callback.  If Hyper-V setup failed in\nhyperv_init(), the kernel will still report that it\u0027s running under\nHyper-V, but will have silently disabled nearly all functionality.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000010\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: 0000 [#1] SMP\n  CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:set_hv_tscchange_cb+0x15/0xa0\n  Code: \u003c8b\u003e 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08\n  ...\n  Call Trace:\n   kvm_arch_init+0x17c/0x280\n   kvm_init+0x31/0x330\n   vmx_init+0xba/0x13a\n   do_one_initcall+0x41/0x1c0\n   kernel_init_freeable+0x1f2/0x23b\n   kernel_init+0x16/0x120\n   ret_from_fork+0x22/0x30"
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: x86/hyperv: Se corrige la desreferencia NULL en set_hv_tscchange_cb() si falla la configuraci\u00f3n de Hyper-V. Verifique si hay una matriz hv_vp_index v\u00e1lida antes de desreferenciar hv_vp_index al configurar la devoluci\u00f3n de llamada de cambio de TSC de Hyper-V. Si la configuraci\u00f3n de Hyper-V fall\u00f3 en hyperv_init(), el kernel a\u00fan informar\u00e1 que se est\u00e1 ejecutando bajo Hyper-V, pero habr\u00e1 deshabilitado silenciosamente casi todas las funciones. ERROR: desreferencia de puntero NULL del kernel, direcci\u00f3n: 0000000000000010 #PF: acceso de lectura del supervisor en modo kernel #PF: error_code(0x0000) - p\u00e1gina no presente PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 4 PID: 1 Comm: swapper/0 No contaminado 5.15.0-rc2+ #75 Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:set_hv_tscchange_cb+0x15/0xa0 C\u00f3digo: \u0026lt;8b\u0026gt; 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08 ... Seguimiento de llamadas: kvm_arch_init+0x17c/0x280 kvm_init+0x31/0x330 vmx_init+0xba/0x13a do_one_initcall+0x41/0x1c0 kernel_init_freeable+0x1f2/0x23b kernel_init+0x16/0x120 ret_from_fork+0x22/0x30"
          }
        ],
        "id": "CVE-2021-47217",
        "lastModified": "2026-06-17T04:16:55.890",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2021-47217",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-06-17T18:03:45.646426Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2024-04-10T19:15:48.813",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-476"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2025-11-21T14:02:59+00:00",
      "cve": "CVE-2021-47217",
      "id": "CVE-2021-47217",
      "initial_release_date": "2021-01-01T00:00:00+00:00",
      "product_status:known_affected": "198",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-47217.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-13T23:56:40Z",
      "cve": "CVE-2021-47217",
      "id": "CVE-2021-47217",
      "initial_release_date": "2024-04-15T23:20:41Z",
      "product_status:known_affected": "402",
      "product_status:known_not_affected": "167",
      "product_status:recommended": "532",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2021-47217",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-47217.json",
      "version": "51"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2024-08-04T05:32:07.432Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
            },
            "references": [
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2021-47217",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2024-06-17T18:03:45.646426Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2024-06-17T18:03:46.614Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Linux",
              "programFiles": [
                "arch/x86/hyperv/hv_init.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "lessThan": "b20ec58f8a6f4fef32cc71480ddf824584e24743",
                  "status": "affected",
                  "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                  "versionType": "git"
                },
                {
                  "lessThan": "b0e44dfb4e4c699cca33ede431b8d127e6e8d661",
                  "status": "affected",
                  "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                  "versionType": "git"
                },
                {
                  "lessThan": "9c177eee116cf888276d3748cb176e72562cfd5c",
                  "status": "affected",
                  "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                  "versionType": "git"
                },
                {
                  "lessThan": "8823ea27fff6084bbb4bc71d15378fae0220b1d8",
                  "status": "affected",
                  "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                  "versionType": "git"
                },
                {
                  "lessThan": "daf972118c517b91f74ff1731417feb4270625a4",
                  "status": "affected",
                  "version": "93286261de1b46339aa27cd4c639b21778f6cade",
                  "versionType": "git"
                }
              ]
            },
            {
              "defaultStatus": "affected",
              "product": "Linux",
              "programFiles": [
                "arch/x86/hyperv/hv_init.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "status": "affected",
                  "version": "4.16"
                },
                {
                  "lessThan": "4.16",
                  "status": "unaffected",
                  "version": "0",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "4.19.*",
                  "status": "unaffected",
                  "version": "4.19.218",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.4.*",
                  "status": "unaffected",
                  "version": "5.4.162",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.10.*",
                  "status": "unaffected",
                  "version": "5.10.82",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.15.*",
                  "status": "unaffected",
                  "version": "5.15.5",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "*",
                  "status": "unaffected",
                  "version": "5.16",
                  "versionType": "original_commit_for_fix"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails\n\nCheck for a valid hv_vp_index array prior to derefencing hv_vp_index when\nsetting Hyper-V\u0027s TSC change callback.  If Hyper-V setup failed in\nhyperv_init(), the kernel will still report that it\u0027s running under\nHyper-V, but will have silently disabled nearly all functionality.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000010\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: 0000 [#1] SMP\n  CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:set_hv_tscchange_cb+0x15/0xa0\n  Code: \u003c8b\u003e 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08\n  ...\n  Call Trace:\n   kvm_arch_init+0x17c/0x280\n   kvm_init+0x31/0x330\n   vmx_init+0xba/0x13a\n   do_one_initcall+0x41/0x1c0\n   kernel_init_freeable+0x1f2/0x23b\n   kernel_init+0x16/0x120\n   ret_from_fork+0x22/0x30"
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2024-12-19T07:37:36.278Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743"
            },
            {
              "url": "https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661"
            },
            {
              "url": "https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c"
            },
            {
              "url": "https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8"
            },
            {
              "url": "https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4"
            }
          ],
          "title": "x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails",
          "x_generator": {
            "engine": "bippy-5f407fcff5a0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2021-47217",
        "datePublished": "2024-04-10T19:01:56.419Z",
        "dateReserved": "2024-04-10T18:59:19.528Z",
        "dateUpdated": "2024-12-19T07:37:36.278Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}



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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.