vsock/vmci: fix UAF when peer resets connection during handshake

{
  "id": "9f4a3b9e16d648f319982a9ad14f5cf7d4315a0f3e03789c141c4995183d6d21",
  "url": "https://osv.dev/vulnerability/CVE-2026-64115",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "vsock/vmci: fix UAF when peer resets connection during handshake",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: vsock/vmci: fix UAF when peer resets connection during handshake vmci_transport_recv_connecting_server() returned err = 0 for a peer RST in its default switch arm: err = pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST ? 0 : -EINVAL; That made vmci_transport_recv_listen() skip vsock_remove_pending(), leaving the pending socket on the listener's pending_links with sk_state = TCP_CLOSE while destroy: still dropped the explicit reference taken before schedule_delayed_work(). One second later vsock_pending_work() observed is_pending=true and performed full cleanup: vsock_remove_pending() then the two trailing sock_put(sk) calls -- the first reached refcount 0 and __sk_freed the socket, and the second wrote into the freed object: BUG: KASAN: slab-use-after-free in refcount_warn_saturate Write of size 4 at addr ffff88800b1cac80 by task kworker Workqueue: events vsock_pending_work Treat peer RST like any other unexpected packet type (err = -EINVAL). All destroy: arms now return err < 0, so vmci_transport_recv_listen() removes pending from pending_links synchronously and vsock_pending_work() takes the is_pending=false / !rejected branch, dropping only its own work reference. This also closes the multi-packet race Sashiko reported on v2: pending is removed from the list before any subsequent packet can find it. The pre-existing sk_acceptq_removed() gap on the err < 0 path of vmci_transport_recv_listen() that Sashiko also n",
    "evidence": "osv:CVE-2026-64115",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.10.258",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.15.209",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.175",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.142",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.92",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.34",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.0.11",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-64115",
      "aliases": [
        "CVE-2026-64115"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
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              "type": "GIT",
              "events": [
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                {
                  "fixed": "1e19f08552b90070ed18bafb1763c78297823af6"
                },
                {
                  "fixed": "1dd531e28f61edd286edc486ab068f135b5ae1eb"
                },
                {
                  "fixed": "ecda37f8faab3220da199335e42564cb7a9ad145"
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          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64115.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
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                  "introduced": "3.9.0"
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                {
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              ]
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64115.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:25.863758823Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1dd531e28f61edd286edc486ab068f135b5ae1eb",
        "https://git.kernel.org/stable/c/1e19f08552b90070ed18bafb1763c78297823af6",
        "https://git.kernel.org/stable/c/440447699c681e26ed58e9c309cad718270a18b4",
        "https://git.kernel.org/stable/c/47e63077605c6c2aa45b3df9847a8cdc1f1f6ef9",
        "https://git.kernel.org/stable/c/99e22ddf4edb63dc8382bc028af928056d3450cf",
        "https://git.kernel.org/stable/c/9fe74e42914c851d68069713b7b917a9c33faf26",
        "https://git.kernel.org/stable/c/cc27e989a5dfdfcfc1cca7c3be27a0c7532b46cb",
        "https://git.kernel.org/stable/c/ecda37f8faab3220da199335e42564cb7a9ad145",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64115.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-64115",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64115.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-64115",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 492556,
  "published_at": "2026-07-19T15:40:15.513+00:00"
}