{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "ee122c79d4227f6ec642157834b6a90fcffa4382"
            },
            {
              "fixed": "0d13b5a413bffc8718b3821b78537ccc6596c233"
            },
            {
              "fixed": "bfb74c48ac2d31476d5e09cf9658844508d2608a"
            },
            {
              "fixed": "081f22177d9d12b1e381b787f203cd5f47508187"
            },
            {
              "fixed": "be83178bfc44588f6e3adb827ed874c683193466"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.3.0"
            },
            {
              "fixed": "6.12.111"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.53"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97965.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: initialize _md in vxlan_xmit_one()\n\nIf a VXLAN device is configured with both VXLAN_F_COLLECT_METADATA and\nVXLAN_F_GBP, and a packet is transmitted through it using an external\nip_tunnel_info that lacks the IP_TUNNEL_VXLAN_OPT_BIT flag, md is left\npointing to the uninitialized _md stack variable:\n\n                if (test_bit(IP_TUNNEL_VXLAN_OPT_BIT, info-\u003ekey.tun_flags)) {\n                        if (info-\u003eoptions_len \u003c sizeof(*md))\n                                goto drop;\n                        md = ip_tunnel_info_opts(info);\n                }\n\nBecause IP_TUNNEL_VXLAN_OPT_BIT is not set, md is not updated and remains\npointing to _md. Later, vxlan_build_skb() is called with md, which\neventually calls vxlan_build_gbp_hdr():\n\n        if (vxflags \u0026 VXLAN_F_GBP)\n                vxlan_build_gbp_hdr(vxh, md);\n\nInside vxlan_build_gbp_hdr(), md-\u003egbp is read:\n\n        if (!md-\u003egbp)\n                return;\n        gbp = (struct vxlanhdr_gbp *)vxh;\n        ...\n        if (md-\u003egbp \u0026 VXLAN_GBP_DONT_LEARN)\n                gbp-\u003edont_learn = 1;\n\nIf the stack contains garbage, this causes:\n1) VXLAN_HF_GBP flag to be spuriously set in the VXLAN header.\n2) gbp-\u003edont_learn and gbp-\u003epolicy_applied to be set from stack bits.\n3) gbp-\u003epolicy_id to receive 16 bits of uninitialized kernel stack data,\n   leaking it onto the wire.\n\nFix this by zero-initializing _md. If IP_TUNNEL_VXLAN_OPT_BIT is not\npresent, md-\u003egbp remains 0, and vxlan_build_gbp_hdr() returns early\nwithout modifying the VXLAN header.",
  "id": "CVE-2026-97965",
  "modified": "2026-09-27T03:30:18.378911100Z",
  "published": "2026-09-25T10:23:07.952Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/081f22177d9d12b1e381b787f203cd5f47508187"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0d13b5a413bffc8718b3821b78537ccc6596c233"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/be83178bfc44588f6e3adb827ed874c683193466"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bfb74c48ac2d31476d5e09cf9658844508d2608a"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97965.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-97965"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "vxlan: initialize _md in vxlan_xmit_one()"
}