FKIE_CVE-2021-47255

Vulnerability from fkie_nvd - Published: 2024-05-21 15:15 - Updated: 2026-06-17 04:17
Severity
7.1 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: kvm: LAPIC: Restore guard to prevent illegal APIC register access Per the SDM, "any access that touches bytes 4 through 15 of an APIC register may cause undefined behavior and must not be executed." Worse, such an access in kvm_lapic_reg_read can result in a leak of kernel stack contents. Prior to commit 01402cf81051 ("kvm: LAPIC: write down valid APIC registers"), such an access was explicitly disallowed. Restore the guard that was removed in that commit.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 5.13
linux linux_kernel 5.13
linux linux_kernel 5.13
linux linux_kernel 5.13
linux linux_kernel 5.13
linux linux_kernel 5.13
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/lapic.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "bf99ea52970caeb4583bdba1192c1f9b53b12c84",
              "status": "affected",
              "version": "01402cf81051f796dac7c60ca11d6147153ca46a",
              "versionType": "git"
            },
            {
              "lessThan": "018685461a5b9a9a70e664ac77aef0d7415a3fd5",
              "status": "affected",
              "version": "01402cf81051f796dac7c60ca11d6147153ca46a",
              "versionType": "git"
            },
            {
              "lessThan": "a2aff09807fbe4018c269d3773a629949058b210",
              "status": "affected",
              "version": "01402cf81051f796dac7c60ca11d6147153ca46a",
              "versionType": "git"
            },
            {
              "lessThan": "218bf772bddd221489c38dde6ef8e917131161f6",
              "status": "affected",
              "version": "01402cf81051f796dac7c60ca11d6147153ca46a",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/lapic.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.3"
            },
            {
              "lessThan": "5.3",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.128",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.46",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.12.*",
              "status": "unaffected",
              "version": "5.12.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "DC847EC3-F5C9-4A5D-B3AE-048BFB665C62",
              "versionEndExcluding": "5.4.128",
              "versionStartIncluding": "5.3",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "59455D13-A902-42E1-97F7-5ED579777193",
              "versionEndExcluding": "5.10.46",
              "versionStartIncluding": "5.5",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7806E7E5-6D4F-4E18-81C1-79B3C60EE855",
              "versionEndExcluding": "5.12.13",
              "versionStartIncluding": "5.11",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "0CBAD0FC-C281-4666-AB2F-F8E6E1165DF7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "96AC23B2-D46A-49D9-8203-8E1BEDCA8532",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "DA610E30-717C-4700-9F77-A3C9244F3BFD",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "1ECD33F5-85BE-430B-8F86-8D7BD560311D",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "CF351855-2437-4CF5-AD7C-BDFA51F27683",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*",
              "matchCriteriaId": "25A855BA-2118-44F2-90EF-EBBB12AF51EF",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkvm: LAPIC: Restore guard to prevent illegal APIC register access\n\nPer the SDM, \"any access that touches bytes 4 through 15 of an APIC\nregister may cause undefined behavior and must not be executed.\"\nWorse, such an access in kvm_lapic_reg_read can result in a leak of\nkernel stack contents. Prior to commit 01402cf81051 (\"kvm: LAPIC:\nwrite down valid APIC registers\"), such an access was explicitly\ndisallowed. Restore the guard that was removed in that commit."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: kvm: LAPIC: Restaurar protecci\u00f3n para evitar el acceso ilegal al registro APIC. Seg\u00fan el SDM, \"cualquier acceso que toque los bytes 4 al 15 de un registro APIC puede causar un comportamiento indefinido y no debe ejecutarse \". Peor a\u00fan, dicho acceso en kvm_lapic_reg_read puede resultar en una fuga del contenido de la pila del kernel. Antes de confirmar 01402cf81051 (\"kvm: LAPIC: anotar registros APIC v\u00e1lidos\"), dicho acceso se prohib\u00eda expl\u00edcitamente. Restaura la guardia que se elimin\u00f3 en esa confirmaci\u00f3n."
    }
  ],
  "id": "CVE-2021-47255",
  "lastModified": "2026-06-17T04:17:01.567",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.2,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-47255",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-05-21T18:50:43.929512Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-05-21T15:15:14.303",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-Other"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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