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FKIE_CVE-2025-21641

Vulnerability from fkie_nvd - Published: 2025-01-19 11:15 - Updated: 2026-06-17 08:43
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: mptcp: sysctl: blackhole timeout: avoid using current->nsproxy As mentioned in the previous commit, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'pernet' structure can be obtained from the table->data using container_of().
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4c74fbdc5ab95b13945be01e6065940b68222db7Mailing List, Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/92cf7a51bdae24a32c592adcdd59a773ae149289Mailing List, Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel 6.13
linux linux_kernel 6.13
linux linux_kernel 6.13
linux linux_kernel 6.13
linux linux_kernel 6.13
linux linux_kernel 6.13
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/mptcp/ctrl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4c74fbdc5ab95b13945be01e6065940b68222db7",
              "status": "affected",
              "version": "27069e7cb3d1cea9377069266acf19b9cc5ad0ae",
              "versionType": "git"
            },
            {
              "lessThan": "92cf7a51bdae24a32c592adcdd59a773ae149289",
              "status": "affected",
              "version": "27069e7cb3d1cea9377069266acf19b9cc5ad0ae",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/mptcp/ctrl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.12"
            },
            {
              "lessThan": "6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "CAA666EC-CF76-46C6-AE86-951E128D4C0A",
              "versionEndExcluding": "6.12.10",
              "versionStartIncluding": "6.12",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "62567B3C-6CEE-46D0-BC2E-B3717FBF7D13",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "5A073481-106D-4B15-B4C7-FB0213B8E1D4",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "DE491969-75AE-4A6B-9A58-8FC5AF98798F",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "93C0660D-7FB8-4FBA-892A-B064BA71E49E",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "034C36A6-C481-41F3-AE9A-D116E5BE6895",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:*",
              "matchCriteriaId": "8AF9DC49-2085-4FFB-A7E3-73DFAFECC7F2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: sysctl: blackhole timeout: avoid using current-\u003ensproxy\n\nAs mentioned in the previous commit, using the \u0027net\u0027 structure via\n\u0027current\u0027 is not recommended for different reasons:\n\n- Inconsistency: getting info from the reader\u0027s/writer\u0027s netns vs only\n  from the opener\u0027s netns.\n\n- current-\u003ensproxy can be NULL in some cases, resulting in an \u0027Oops\u0027\n  (null-ptr-deref), e.g. when the current task is exiting, as spotted by\n  syzbot [1] using acct(2).\n\nThe \u0027pernet\u0027 structure can be obtained from the table-\u003edata using\ncontainer_of()."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: sysctl: blackhole timeout: avoid using current-\u0026gt;nsproxy Como se mencion\u00f3 en el commit anterior, no se recomienda usar la estructura \u0027net\u0027 a trav\u00e9s de \u0027current\u0027 por diferentes razones: - Inconsistencia: obtener informaci\u00f3n de las redes de red del lector/escritor frente a solo de las redes de red del abridor. - current-\u0026gt;nsproxy puede ser NULL en algunos casos, lo que resulta en un \u0027Oops\u0027 (null-ptr-deref), por ejemplo, cuando la tarea actual est\u00e1 saliendo, como lo detect\u00f3 syzbot [1] usando acct(2). La estructura \u0027pernet\u0027 se puede obtener de table-\u0026gt;data usando Container_of()."
    }
  ],
  "id": "CVE-2025-21641",
  "lastModified": "2026-06-17T08:43:54.800",
  "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"
      },
      {
        "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": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-21641",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-10-01T19:54:04.133628Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-01-19T11:15:09.643",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Mailing List",
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/4c74fbdc5ab95b13945be01e6065940b68222db7"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Mailing List",
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/92cf7a51bdae24a32c592adcdd59a773ae149289"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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