{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "3625750f05ecce21a0fce429c1ff85acfffb461b"
            },
            {
              "fixed": "cabfacbd5af09d3ae898ca224c4a1459e9bba15d"
            },
            {
              "fixed": "3f4920d165b29052255527d8ae7619e7ec132ece"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.9.0"
            },
            {
              "fixed": "7.1.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68337.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject redirect helpers without a bpf_net_context\n\nThe bpf_redirect*() helpers and skb_do_redirect() obtain the per-task\nbpf_redirect_info via bpf_net_ctx_get_ri(), which dereferences the\ncurrent-\u003ebpf_net_context unconditionally. That context is established\non the paths that run tc BPF such as sch_handle_{ingress,egress}(),\n*except* for the case where {cls,act}_bpf was attached to a proper\nqdisc. A program running from there reaches the NULL deref in two ways:\n\n* It calls bpf_redirect() directly, which dereferences the context at\n  the top of the helper:\n\n     tc qdisc add dev eth0 root handle 1: red limit 1MB min 10KB max 20KB \\\n        avpkt 1000 burst 100 qevent early_drop block 10\n     tc filter add block 10 pref 1 bpf obj redirect.o\n\n* It simply returns TC_ACT_REDIRECT without helper call: tcf_qevent_handle()\n  then dispatches to skb_do_redirect(), which dereferences the context\n\nRather than extending bpf_net_context management into the qdisc path,\nmake the redirect helpers refuse to operate when no context exists, and\nhave tcf_qevent_handle() drop a TC_ACT_REDIRECT verdict instead of\ncalling skb_do_redirect(). Previous behaviour was a crash, so nothing\nregresses by not supporting it.",
  "id": "CVE-2026-68337",
  "modified": "2026-08-18T03:31:11.240281597Z",
  "published": "2026-08-10T12:03:13.583Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3f4920d165b29052255527d8ae7619e7ec132ece"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cabfacbd5af09d3ae898ca224c4a1459e9bba15d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68337.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68337"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "bpf: Reject redirect helpers without a bpf_net_context"
}