FKIE_CVE-2021-47293

Vulnerability from fkie_nvd - Published: 2024-05-21 15:15 - Updated: 2026-06-17 04:17
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_skbmod: Skip non-Ethernet packets Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2 protocol, which is not always the case. As an example, for CAN devices: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocol ip prio 10 \ matchall action skbmod swap mac Doing the above silently corrupts all the packets. Do not perform skbmod actions for non-Ethernet packets.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57bPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0dPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0cPatch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57bPatch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0dPatch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0cPatch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 5.14
linux linux_kernel 5.14
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_skbmod.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "e4fdca366806f6bab374d1a95e626a10a3854b0c",
              "status": "affected",
              "version": "86da71b57383d40993cb90baafb3735cffe5d800",
              "versionType": "git"
            },
            {
              "lessThan": "a88414fb1117f2fe65fb88e45ba694e1d09d5024",
              "status": "affected",
              "version": "86da71b57383d40993cb90baafb3735cffe5d800",
              "versionType": "git"
            },
            {
              "lessThan": "071729150be9e1d1b851b70efb6d91ee9269d57b",
              "status": "affected",
              "version": "86da71b57383d40993cb90baafb3735cffe5d800",
              "versionType": "git"
            },
            {
              "lessThan": "34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d",
              "status": "affected",
              "version": "86da71b57383d40993cb90baafb3735cffe5d800",
              "versionType": "git"
            },
            {
              "lessThan": "727d6a8b7ef3d25080fad228b2c4a1d4da5999c6",
              "status": "affected",
              "version": "86da71b57383d40993cb90baafb3735cffe5d800",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_skbmod.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.9"
            },
            {
              "lessThan": "4.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.19.*",
              "status": "unaffected",
              "version": "4.19.199",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.136",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.54",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.13.*",
              "status": "unaffected",
              "version": "5.13.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "44776629-4D21-459F-A55F-103B063D3F6C",
              "versionEndExcluding": "4.19.199",
              "versionStartIncluding": "4.9",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "E1FCD98C-8886-4844-B7AF-C42731DF9465",
              "versionEndExcluding": "5.4.136",
              "versionStartIncluding": "4.20",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "1BD5A2EE-859F-40FC-BDAC-167AAE37C870",
              "versionEndExcluding": "5.10.54",
              "versionStartIncluding": "5.5",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "512C22FC-1524-4E6F-9E62-4F4B7B6E0576",
              "versionEndExcluding": "5.13.6",
              "versionStartIncluding": "5.11",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "71268287-21A8-4488-AA4F-23C473153131",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "23B9E5C6-FAB5-4A02-9E39-27C8787B0991",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_skbmod: Skip non-Ethernet packets\n\nCurrently tcf_skbmod_act() assumes that packets use Ethernet as their L2\nprotocol, which is not always the case.  As an example, for CAN devices:\n\n\t$ ip link add dev vcan0 type vcan\n\t$ ip link set up vcan0\n\t$ tc qdisc add dev vcan0 root handle 1: htb\n\t$ tc filter add dev vcan0 parent 1: protocol ip prio 10 \\\n\t\tmatchall action skbmod swap mac\n\nDoing the above silently corrupts all the packets.  Do not perform skbmod\nactions for non-Ethernet packets."
    },
    {
      "lang": "es",
      "value": " En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/sched: act_skbmod: omitir paquetes que no sean Ethernet. Actualmente, tcf_skbmod_act() asume que los paquetes usan Ethernet como protocolo L2, lo cual no siempre es el caso. Como ejemplo, para dispositivos CAN: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocolo ip prio 10 \\ matchall action skbmod swap mac Hacer lo anterior corrompe silenciosamente todos los paquetes. No realice acciones de skbmod para paquetes que no sean Ethernet."
    }
  ],
  "id": "CVE-2021-47293",
  "lastModified": "2026-06-17T04:17:07.313",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-47293",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-05-28T19:25:44.173169Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-05-21T15:15:17.243",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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