can: dev: init_can_skb(): restore skb header initialization

{
  "id": "683aaad019c863d05f7b86afa3fdcf0f38d54bab4077973b17ada2dbf6cee532",
  "url": "https://osv.dev/vulnerability/CVE-2026-99066",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "can: dev: init_can_skb(): restore skb header initialization",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: can: dev: init_can_skb(): restore skb header initialization Commit 9f10374bb024 (\"can: remove private CAN skb headroom infrastructure\") removed the skb_reset_mac_header()/skb_reset_network_header()/ skb_reset_transport_header() calls from init_can_skb(). As a result, RX skbs from alloc_can_skb() and friends again carry mac_header = 0xFFFF. When such an skb reaches packet_rcv_spkt() (SOCK_PACKET), the push length calculation overflows and triggers skb_under_panic -> kernel BUG -> full machine panic. The same issue was originally reported in 2014 on linux-can and fixed by commit 969439016d2c (\"can: add missing initialisations in CAN related skbuffs\"). packet_rcv_spkt() itself has never been hardened: only packet_rcv() and tpacket_rcv() gained dev_has_header() checks in commit d549699048b4 (\"net/packet: fix packet receive on L3 devices without visible hard header\").",
    "evidence": "osv:CVE-2026-99066",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "7.2.11",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-99066",
      "aliases": [
        "CVE-2026-99066"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "9f10374bb024593a611e6845847f0444841a231b"
                },
                {
                  "fixed": "8078375dfd0baecd9f1b7b06bb2d6f88d7cb8632"
                },
                {
                  "fixed": "0a04c0cb8606ff88399489d03ef255afe90d0d5f"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-99066.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "7.0.0"
                },
                {
                  "fixed": "7.2.11"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-99066.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:41.201968251Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/0a04c0cb8606ff88399489d03ef255afe90d0d5f",
        "https://git.kernel.org/stable/c/8078375dfd0baecd9f1b7b06bb2d6f88d7cb8632",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99066.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-99066",
        "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/2026/99xxx/CVE-2026-99066.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-99066",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 509111,
  "published_at": "2026-10-23T12:23:09.516+00:00"
}