{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "5a963eb61b7c39e6c422b6e48619d19d04719358"
            },
            {
              "fixed": "2e151c74bcc53e3ed313bd1c21b0d5bb442edbc0"
            },
            {
              "fixed": "ba72ed1c8476ce68eb7152dfcbc5330cefcbaa91"
            },
            {
              "fixed": "b14a682ad7d45345701e08f9279d483a1da8b36c"
            },
            {
              "fixed": "f5b143f4cd3fb7673df8d727550478a4b762908a"
            },
            {
              "fixed": "2d06cb25a497d3a7034ef9d172626c2d6620a0f1"
            },
            {
              "fixed": "8f27260b989f488760289276377db24fbfb20bfa"
            },
            {
              "fixed": "8bc60db48e8cba35488bbd6e1f94aa990afa275a"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.16.0"
            },
            {
              "fixed": "5.15.224"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.191"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.160"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.114"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.58"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99041.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nip6_gre: remove obsolete ERSPAN PMTU update\n\nA tc tunnel_key action can attach a METADATA_IP_TUNNEL dst to an skb,\nand mirred can redirect it to a native ip6erspan device. The legacy PMTU\nupdate in ip6erspan_tunnel_xmit() treats that metadata dst as a route.\nSince it has no output device, dst_dev(dst)-\u003emtu dereferences NULL.\n\nOn v7.2 with KASAN, an initial UID/GID 65534 process with CapEff 0 used\nself-created user and network namespaces to trigger:\n\n  KASAN: null-ptr-deref\n  RIP: ip6erspan_tunnel_xmit+0x10fc/0x2cc0\n  Kernel panic - not syncing: Fatal exception in interrupt\n\nThe update is obsolete. Commit fe1a4ca0a2b7 (\"ip6_gre: process toobig\nin a better way\") changed IPv6 GRE Too Big handling to update the\nunderlay route and removed the equivalent block from __gre6_xmit().\nip6_tnl_xmit() then propagates the underlay PMTU to the overlay route.\n\nRemove the stale ERSPAN copy and its now-unused dst variable. This\neliminates the metadata-dst dereference and keeps ERSPAN aligned with\nIPv6 GRE PMTU handling.",
  "id": "CVE-2026-99041",
  "modified": "2026-11-01T02:30:39.042296487Z",
  "published": "2026-10-23T12:22:00.403Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2d06cb25a497d3a7034ef9d172626c2d6620a0f1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2e151c74bcc53e3ed313bd1c21b0d5bb442edbc0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8bc60db48e8cba35488bbd6e1f94aa990afa275a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8f27260b989f488760289276377db24fbfb20bfa"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b14a682ad7d45345701e08f9279d483a1da8b36c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ba72ed1c8476ce68eb7152dfcbc5330cefcbaa91"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f5b143f4cd3fb7673df8d727550478a4b762908a"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99041.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99041"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.2",
  "summary": "ip6_gre: remove obsolete ERSPAN PMTU update"
}