Vulnerability-Lookup

FKIE_CVE-2025-21669

Vulnerability from fkie_nvd - Published: 2025-01-31 12:15 - Updated: 2026-07-30 06:18

Severity

7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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: vsock/virtio: discard packets if the transport changes If the socket has been de-assigned or assigned to another transport, we must discard any packets received because they are not expected and would cause issues when we access vsk->transport. A possible scenario is described by Hyunwoo Kim in the attached link, where after a first connect() interrupted by a signal, and a second connect() failed, we can find `vsk->transport` at NULL, leading to a NULL pointer dereference.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/18a7fc371d1dbf8deff16c2dd9292bcc73f43040	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6486915fa661584d70e8e7e4068c6c075c67dd6d	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/677579b641af109613564460a4e3bdcb16850b61	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/88244163bc7e7b0ce9dd7bf4c8a563b41525c3ee	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d88b249e14bd0ee1e46bbe4f456e22e01b8c68de	Patch
af854a3a-2127-422b-91ae-364da2661108	https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
af854a3a-2127-422b-91ae-364da2661108	https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html
0b142b55-0307-4c5a-b3c9-f314f3fb7c5e	https://cert-portal.siemens.com/productcert/html/ssa-265688.html

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
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
linux	linux_kernel	6.13

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/vmw_vsock/virtio_transport_common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
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              "version": "c0cfa2d8a788fcf45df5bf4070ab2474c88d543a",
              "versionType": "git"
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          ]
        },
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          "defaultStatus": "affected",
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          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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              "status": "unaffected",
              "version": "5.10.234",
              "versionType": "semver"
            },
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              "status": "unaffected",
              "version": "5.15.177",
              "versionType": "semver"
            },
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              "status": "unaffected",
              "version": "6.1.127",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.74",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.13",
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            }
          ]
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      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "affectedData": [
        {
          "defaultStatus": "unknown",
          "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
          "vendor": "Siemens",
          "versions": [
            {
              "lessThan": "*",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
    }
  ],
  "configurations": [
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      "nodes": [
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              "vulnerable": true
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          ],
          "negate": false,
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      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/virtio: discard packets if the transport changes\n\nIf the socket has been de-assigned or assigned to another transport,\nwe must discard any packets received because they are not expected\nand would cause issues when we access vsk-\u003etransport.\n\nA possible scenario is described by Hyunwoo Kim in the attached link,\nwhere after a first connect() interrupted by a signal, and a second\nconnect() failed, we can find `vsk-\u003etransport` at NULL, leading to a\nNULL pointer dereference."
    },
    {
      "lang": "es",
      "value": "En el kernel Linux, se ha resuelto la siguiente vulnerabilidad: vsock/virtio: descartar paquetes si cambia el transporte Si el socket ha sido desasignado o asignado a otro transporte, debemos descartar cualquier paquete recibido porque no son los esperados y causar\u00edan problemas cuando accedamos a vsk-\u0026gt;transport. Un posible escenario es descrito por Hyunwoo Kim en el enlace adjunto, donde despu\u00e9s de un primer connect() interrumpido por una se\u00f1al, y un segundo connect() fallido, podemos encontrar `vsk-\u0026gt;transport` en NULL, lo que lleva a una desreferencia de puntero NULL."
    }
  ],
  "id": "CVE-2025-21669",
  "lastModified": "2026-07-30T06:18:13.990",
  "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": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      },
      {
        "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-2025-21669",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-10-01T19:52:17.860929Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-01-31T12:15:28.053",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/18a7fc371d1dbf8deff16c2dd9292bcc73f43040"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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      "url": "https://git.kernel.org/stable/c/2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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    },
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    },
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    },
    {
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      "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"
    },
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      "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"
    },
    {
      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
    }
  ],
  "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"
    }
  ]
}

CVE-2025-21669 (GCVE-0-2025-21669)

Vulnerability from cvelistv5 – Published: 2025-01-31 11:25 – Updated: 2026-08-05 11:53

Title

vsock/virtio: discard packets if the transport changes

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

5.5 (Medium)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-10-01 19:52 UTC

CWE

CWE-476 - NULL Pointer Dereference

Assigner

Linux mitre root

References

9 references

URL	Tags
https://git.kernel.org/stable/c/18a7fc371d1dbf8de…
https://git.kernel.org/stable/c/6486915fa661584d7…
https://git.kernel.org/stable/c/88244163bc7e7b0ce…
https://git.kernel.org/stable/c/d88b249e14bd0ee1e…
https://git.kernel.org/stable/c/677579b641af10961…
https://git.kernel.org/stable/c/2cb7c756f605ec02f…
https://lists.debian.org/debian-lts-announce/2025…
https://lists.debian.org/debian-lts-announce/2025…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

3 products

Vendor	Product	Version
Linux	Linux	Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 18a7fc371d1dbf8deff16c2dd9292bcc73f43040 (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 6486915fa661584d70e8e7e4068c6c075c67dd6d (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 88244163bc7e7b0ce9dd7bf4c8a563b41525c3ee (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < d88b249e14bd0ee1e46bbe4f456e22e01b8c68de (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 677579b641af109613564460a4e3bdcb16850b61 (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 (git)
Linux	Linux	Affected: 5.5 Unaffected: 0 , < 5.5 (semver) Unaffected: 5.10.234 , ≤ 5.10.* (semver) Unaffected: 5.15.177 , ≤ 5.15.* (semver) Unaffected: 6.1.127 , ≤ 6.1.* (semver) Unaffected: 6.6.74 , ≤ 6.6.* (semver) Unaffected: 6.12.11 , ≤ 6.12.* (semver) Unaffected: 6.13 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC S7-1500 TM MFP - GNU/Linux subsystem	Affected: 0 , < * (custom)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "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"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2025-21669",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-10-01T19:52:17.860929Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-476",
                "description": "CWE-476 NULL Pointer Dereference",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-10-01T19:57:12.459Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-03T20:58:50.209Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"
          },
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "affected": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-12T12:03:09.412Z",
          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
        },
        "references": [
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
          }
        ],
        "x_adpType": "supplier"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/vmw_vsock/virtio_transport_common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "18a7fc371d1dbf8deff16c2dd9292bcc73f43040",
              "status": "affected",
              "version": "c0cfa2d8a788fcf45df5bf4070ab2474c88d543a",
              "versionType": "git"
            },
            {
              "lessThan": "6486915fa661584d70e8e7e4068c6c075c67dd6d",
              "status": "affected",
              "version": "c0cfa2d8a788fcf45df5bf4070ab2474c88d543a",
              "versionType": "git"
            },
            {
              "lessThan": "88244163bc7e7b0ce9dd7bf4c8a563b41525c3ee",
              "status": "affected",
              "version": "c0cfa2d8a788fcf45df5bf4070ab2474c88d543a",
              "versionType": "git"
            },
            {
              "lessThan": "d88b249e14bd0ee1e46bbe4f456e22e01b8c68de",
              "status": "affected",
              "version": "c0cfa2d8a788fcf45df5bf4070ab2474c88d543a",
              "versionType": "git"
            },
            {
              "lessThan": "677579b641af109613564460a4e3bdcb16850b61",
              "status": "affected",
              "version": "c0cfa2d8a788fcf45df5bf4070ab2474c88d543a",
              "versionType": "git"
            },
            {
              "lessThan": "2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1",
              "status": "affected",
              "version": "c0cfa2d8a788fcf45df5bf4070ab2474c88d543a",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/vmw_vsock/virtio_transport_common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.5"
            },
            {
              "lessThan": "5.5",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.234",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.177",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.127",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.74",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.234",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.177",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.127",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.74",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.11",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.13",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/virtio: discard packets if the transport changes\n\nIf the socket has been de-assigned or assigned to another transport,\nwe must discard any packets received because they are not expected\nand would cause issues when we access vsk-\u003etransport.\n\nA possible scenario is described by Hyunwoo Kim in the attached link,\nwhere after a first connect() interrupted by a signal, and a second\nconnect() failed, we can find `vsk-\u003etransport` at NULL, leading to a\nNULL pointer dereference."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The vulnerability is reached through AF_VSOCK socket syscalls (`connect()`) plus packets delivered by the local `vsock_loopback` transport, all from a local process. Per kernel scoring guidance vsock is Local.\nAC:L - The attacker controls every element: both `connect()` calls, the interrupting signal (self-delivered via `alarm()`/`pthread_kill()`), the peer socket that times the RESPONSE, and the RST/SHUTDOWN packet, and the sequence can be retried indefinitely.\nPR:L - `vsock_create()` performs no capability check and `CONFIG_VSOCKETS_LOOPBACK` is `default y`, so any unprivileged local user can create AF_VSOCK sockets, auto-bind an ephemeral port, and inject loopback packets.\nUI:N - The entire sequence \u2014 double connect, signal, packet injection \u2014 is performed by the attacker\u0027s own process with no victim action required.\nS:U - The corruption and crash are confined to the kernel of the machine running the attacker\u0027s process; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - When the socket has been reassigned to a non-virtio transport, `vsk-\u003etrans` is type-confused as `struct virtio_vsock_sock`, letting the receive path read and act on mistyped heap state (mistyped `sk_buff_head` in `virtio_transport_recv_enqueue()`, `container_of` on a non-`virtio_transport` ops struct), which is leverageable for arbitrary kernel memory disclosure.\nI:H - The same type confusion writes two fully attacker-controlled 32-bit header values (`buf_alloc`/`fwd_cnt`) into the middle of a differently-typed heap object (over `qpair`/`produce_size` in `struct vmci_transport`) and performs an indirect call through `t_ops-\u003esend_pkt` derived from a bogus `container_of`, giving a controlled-write and control-flow hijack primitive.\nA:H - The confirmed and reported impact is a NULL pointer dereference at `vsk-\u003etransport-\u003estream_has_data()` while the socket lock is held, producing a kernel oops/panic that an unprivileged user can trigger on demand."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:53:30.113Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/18a7fc371d1dbf8deff16c2dd9292bcc73f43040"
        },
        {
          "url": "https://git.kernel.org/stable/c/6486915fa661584d70e8e7e4068c6c075c67dd6d"
        },
        {
          "url": "https://git.kernel.org/stable/c/88244163bc7e7b0ce9dd7bf4c8a563b41525c3ee"
        },
        {
          "url": "https://git.kernel.org/stable/c/d88b249e14bd0ee1e46bbe4f456e22e01b8c68de"
        },
        {
          "url": "https://git.kernel.org/stable/c/677579b641af109613564460a4e3bdcb16850b61"
        },
        {
          "url": "https://git.kernel.org/stable/c/2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1"
        }
      ],
      "title": "vsock/virtio: discard packets if the transport changes",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21669",
    "datePublished": "2025-01-31T11:25:33.185Z",
    "dateReserved": "2024-12-29T08:45:45.735Z",
    "dateUpdated": "2026-08-05T11:53:30.113Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.