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CVE-2026-64575

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: tcp: fix double sock release on batch realloc bpf_iter_tcp_batch() releases the current batch via bpf_iter_tcp_put_batch(), which drops the socket refs and rewrites each slot with the socket cookie, then grows the batch. cur_sk/end_sk are kept for bpf_iter_tcp_resume(), but on realloc failure the function returns ERR_PTR() before resume runs, leaving cur_sk < end_sk over slots that now hold cookies rather than sock pointers. bpf_iter_tcp_seq_stop() then calls bpf_iter_tcp_put_batch() again and dereferences a cookie as a struct sock. Empty the batch on the failure path so stop() does not release it again. The sockets were already freed by the first bpf_iter_tcp_put_batch(), so nothing leaks, and a later read() rescans the bucket from the start instead of skipping it. The sibling GFP_NOWAIT failure path still holds real socket references and is left for stop() to release. BUG: KASAN: null-ptr-deref in __sock_gen_cookie Read of size 8 at addr 0000000000000059 by task exploit ... __sock_gen_cookie (net/core/sock_diag.c:28) bpf_iter_tcp_put_batch (net/ipv4/tcp_ipv4.c:2918) bpf_iter_tcp_seq_stop (net/ipv4/tcp_ipv4.c:3270) bpf_seq_read (kernel/bpf/bpf_iter.c:205) vfs_read (fs/read_write.c:572) ksys_read (fs/read_write.c:716) do_syscall_64 entry_SYSCALL_64_after_hwframe Kernel panic - not syncing: Fatal exception

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-05 08:16:37.363000
Last modified
2026-10-19 21:17:47.840000
View original CVE JSON
{
  "id": "CVE-2026-64575",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-05T08:16:37.363",
  "lastModified": "2026-10-19T21:17:47.840",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: tcp: fix double sock release on batch realloc\n\nbpf_iter_tcp_batch() releases the current batch via\nbpf_iter_tcp_put_batch(), which drops the socket refs and rewrites\neach slot with the socket cookie, then grows the batch. cur_sk/end_sk\nare kept for bpf_iter_tcp_resume(), but on realloc failure the function\nreturns ERR_PTR() before resume runs, leaving cur_sk < end_sk over\nslots that now hold cookies rather than sock pointers.\nbpf_iter_tcp_seq_stop() then calls bpf_iter_tcp_put_batch() again and\ndereferences a cookie as a struct sock.\n\nEmpty the batch on the failure path so stop() does not release it\nagain. The sockets were already freed by the first\nbpf_iter_tcp_put_batch(), so nothing leaks, and a later read() rescans\nthe bucket from the start instead of skipping it. The sibling\nGFP_NOWAIT failure path still holds real socket references and is left\nfor stop() to release.\n\n  BUG: KASAN: null-ptr-deref in __sock_gen_cookie\n  Read of size 8 at addr 0000000000000059 by task exploit\n   ...\n   __sock_gen_cookie (net/core/sock_diag.c:28)\n   bpf_iter_tcp_put_batch (net/ipv4/tcp_ipv4.c:2918)\n   bpf_iter_tcp_seq_stop (net/ipv4/tcp_ipv4.c:3270)\n   bpf_seq_read (kernel/bpf/bpf_iter.c:205)\n   vfs_read (fs/read_write.c:572)\n   ksys_read (fs/read_write.c:716)\n   do_syscall_64\n   entry_SYSCALL_64_after_hwframe\n  Kernel panic - not syncing: Fatal exception"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/ipv4/tcp_ipv4.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "9794ac757a650dd594391192183c9caf939f8223",
              "lessThan": "c842882e4c5d2818b858d6baf3fd10958c93f729",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1d7a82c1df5fc397eaca9c6b8c8f61aae9866ad4",
              "lessThan": "7a6a6d2a127866935f87b55b557bc89693065462",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "36f955807ee4ede07e9410772f792e4cb4ec807b",
              "lessThan": "f0c1810320b0dac228103fad7311e89532134d83",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "cdec67a489d4fdae3e83e04fca0419136a83c4c2",
              "lessThan": "9f27c4f0ae35b5390ce4f7a54d3501144e41a54d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "cdec67a489d4fdae3e83e04fca0419136a83c4c2",
              "lessThan": "8a726e9585ffe7bfbfad2b5279277a00973970f3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "cdec67a489d4fdae3e83e04fca0419136a83c4c2",
              "lessThan": "980a813452754f8001704744e92f7aa697c53dd3",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/ipv4/tcp_ipv4.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.42",
              "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": "2026-10-16T15:43:09.032103Z",
          "id": "CVE-2026-64575",
          "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/7a6a6d2a127866935f87b55b557bc89693065462",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8a726e9585ffe7bfbfad2b5279277a00973970f3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/980a813452754f8001704744e92f7aa697c53dd3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9f27c4f0ae35b5390ce4f7a54d3501144e41a54d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c842882e4c5d2818b858d6baf3fd10958c93f729",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}