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FKIE_CVE-2025-21759

Vulnerability from fkie_nvd - Published: 2025-02-27 03:15 - Updated: 2026-06-17 08:44
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: extend RCU protection in igmp6_send() igmp6_send() can be called without RTNL or RCU being held. Extend RCU protection so that we can safely fetch the net pointer and avoid a potential UAF. Note that we no longer can use sock_alloc_send_skb() because ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep. Instead use alloc_skb() and charge the net->ipv6.igmp_sk socket under RCU protection.
Impacted products

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv6/mcast.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a",
              "status": "affected",
              "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551",
              "versionType": "git"
            },
            {
              "lessThan": "0bf8e2f3768629d437a32cb824149e6e98254381",
              "status": "affected",
              "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551",
              "versionType": "git"
            },
            {
              "lessThan": "8e92d6a413feaf968a33f0b439ecf27404407458",
              "status": "affected",
              "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551",
              "versionType": "git"
            },
            {
              "lessThan": "087c1faa594fa07a66933d750c0b2610aa1a2946",
              "status": "affected",
              "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv6/mcast.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.26"
            },
            {
              "lessThan": "2.6.26",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.79",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.13.*",
              "status": "unaffected",
              "version": "6.13.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "80691BA5-295B-4772-9338-1D31A39548D6",
              "versionEndExcluding": "6.6.79",
              "versionStartIncluding": "2.6.26",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "13C8DB18-FC60-425F-84E5-3EDDEC61B2FC",
              "versionEndExcluding": "6.12.16",
              "versionStartIncluding": "6.7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "2A2093ED-74A9-43F9-AC72-50030F374EA4",
              "versionEndExcluding": "6.13.4",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "186716B6-2B66-4BD0-852E-D48E71C0C85F",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "0D3E781C-403A-498F-9DA9-ECEE50F41E75",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: extend RCU protection in igmp6_send()\n\nigmp6_send() can be called without RTNL or RCU being held.\n\nExtend RCU protection so that we can safely fetch the net pointer\nand avoid a potential UAF.\n\nNote that we no longer can use sock_alloc_send_skb() because\nipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.\n\nInstead use alloc_skb() and charge the net-\u003eipv6.igmp_sk\nsocket under RCU protection."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ipv6: mcast: extender la protecci\u00f3n RCU en igmp6_send() igmp6_send() se puede llamar sin que se mantenga RTNL o RCU. Extienda la protecci\u00f3n RCU para que podamos obtener de forma segura el puntero de red y evitar un posible UAF. Tenga en cuenta que ya no podemos usar sock_alloc_send_skb() porque ipv6.igmp_sk usa asignaciones GFP_KERNEL que pueden dormir. En su lugar, use alloc_skb() y cargue el socket net-\u0026gt;ipv6.igmp_sk bajo la protecci\u00f3n RCU."
    }
  ],
  "id": "CVE-2025-21759",
  "lastModified": "2026-06-17T08:44:12.443",
  "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": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-21759",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-02-27T17:57:46.460072Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-02-27T03:15:16.550",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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