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CVE-2026-68399

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix UAF in sock clone early bailouts Similar to recent commit 9b51a6155d14 ("bpf,fork: wipe ->bpf_storage before bailouts that access it"), sk_clone() performs an initial shallow copy of the socket field ->sk_bpf_storage via sock_copy() for the cloned socket newsk. If sk_clone() bails out early (e.g. if sk_filter_charge() fails) prior to calling bpf_sk_storage_clone(), newsk->sk_bpf_storage still points to the parent socket's BPF local storage. When newsk is subsequently freed via sk_free(), the deallocation path (__sk_destruct() -> bpf_sk_storage_free()) destroys the parent socket's BPF local storage, leading to a use-after-free (UAF) on the parent socket. Fix this by resetting newsk->sk_bpf_storage to NULL immediately after sock_copy() in sk_clone(), and remove the now redundant initialization from bpf_sk_storage_clone().

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-10 13:20:33.383000
Last modified
2026-10-30 13:19:44.210000
View original CVE JSON
{
  "id": "CVE-2026-68399",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-10T13:20:33.383",
  "lastModified": "2026-10-30T13:19:44.210",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix UAF in sock clone early bailouts\n\nSimilar to recent commit 9b51a6155d14 (\"bpf,fork: wipe ->bpf_storage\nbefore bailouts that access it\"), sk_clone() performs an initial\nshallow copy of the socket field ->sk_bpf_storage via sock_copy()\nfor the cloned socket newsk.\n\nIf sk_clone() bails out early (e.g. if sk_filter_charge() fails) prior\nto calling bpf_sk_storage_clone(), newsk->sk_bpf_storage still points\nto the parent socket's BPF local storage. When newsk is subsequently\nfreed via sk_free(), the deallocation path (__sk_destruct() ->\nbpf_sk_storage_free()) destroys the parent socket's BPF local storage,\nleading to a use-after-free (UAF) on the parent socket.\n\nFix this by resetting newsk->sk_bpf_storage to NULL immediately after\nsock_copy() in sk_clone(), and remove the now redundant initialization\nfrom bpf_sk_storage_clone()."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/core/bpf_sk_storage.c",
            "net/core/sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d",
              "lessThan": "ac855efc6bb216b262b672af68219e5b731f42a4",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d",
              "lessThan": "f6814814b3bdd6ecb6bc1fc53ba4e827e0185f01",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d",
              "lessThan": "24139461545e44442df9b80deace26b2eb3e103d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d",
              "lessThan": "01f8a354497ba739f81b691b3702bc4c46500a4d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d",
              "lessThan": "14b49b5ab29979552c219a09e569b424fbbf4a6e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d",
              "lessThan": "7cbd0c4cebe4c9f678d15e6b9ba975e1155a107f",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/core/bpf_sk_storage.c",
            "net/core/sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.2",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.2",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.57",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.6",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T15:48:12.954788Z",
          "id": "CVE-2026-68399",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/01f8a354497ba739f81b691b3702bc4c46500a4d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7cbd0c4cebe4c9f678d15e6b9ba975e1155a107f",
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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}