{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/vxlan/vxlan_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "9c58c729d32e7cea5772cc44929c6cd61e5a31cd",
              "status": "affected",
              "version": "5602c48cf87562c2f95b831d690631935e834295",
              "versionType": "git"
            },
            {
              "lessThan": "f79c80f173fda9545b220c1f094b65fc06c252d0",
              "status": "affected",
              "version": "5602c48cf87562c2f95b831d690631935e834295",
              "versionType": "git"
            },
            {
              "lessThan": "08f40c0d23c67c3aa4224c3311e134999c721fb4",
              "status": "affected",
              "version": "5602c48cf87562c2f95b831d690631935e834295",
              "versionType": "git"
            },
            {
              "lessThan": "4a8cde6f7281ea2c4c290f9ad9923b3631defceb",
              "status": "affected",
              "version": "5602c48cf87562c2f95b831d690631935e834295",
              "versionType": "git"
            },
            {
              "lessThan": "ef44dac2a37f86eeae6b88ed10a6d60b35387dfd",
              "status": "affected",
              "version": "5602c48cf87562c2f95b831d690631935e834295",
              "versionType": "git"
            },
            {
              "lessThan": "30a45c0bffdd62350261e2f2689fdba426a33578",
              "status": "affected",
              "version": "5602c48cf87562c2f95b831d690631935e834295",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/vxlan/vxlan_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.7"
            },
            {
              "lessThan": "4.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.178",
                  "versionStartIncluding": "4.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "4.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "4.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "4.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "4.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "4.7",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: Fix potential null-ptr-deref in vxlan_gro_prepare_receive().\n\nudp_tunnel_sock_release() could set sk-\u003esk_user_data to NULL\nwhile vxlan_gro_prepare_receive() is running.\n\nLet\u0027s check if rcu_dereference_sk_user_data() is NULL after\nskb_gro_remcsum_init()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The bug is in vxlan_gro_prepare_receive() on the UDP GRO receive path; remote VXLAN/UDP packets reach it via inet_gro_receive\u2192udp4_gro_receive\u2192udp_tunnel_gro_rcv\u2192vxlan_gro_receive during NAPI processing on internet/cloud overlay endpoints.\nAC:L - An attacker can reliably trigger the race by flooding VXLAN GRO packets while concurrently tearing down the VXLAN device (e.g., via CAP_NET_ADMIN in a user namespace); repeated attempts during orchestrated interface churn also make the timing window attacker-driven rather than purely environmental.\nPR:N - Exploitation requires only the ability to send crafted VXLAN UDP traffic to a listening tunnel port; no target credentials or local account are needed, and concurrent teardown can occur from normal administrative or automation activity rather than attacker-held privileges.\nUI:N - No victim interaction is required beyond the host already running a VXLAN interface; the attacker triggers the fault purely by sending network packets timed against interface teardown.\nS:U - Impact is a kernel fault in networking softirq context on the same host; it does not cross VM, container, or IOMMU security boundaries into another authority.\nC:H - The race can leave a stale vxlan_sock pointer after udp_tunnel_sock_release() frees sk_user_data; dereferencing vs-\u003eflags is a use-after-free read that can expose kernel heap contents and is treated as arbitrary read potential under conservative scoring.\nI:H - Use-after-free on the vxlan_sock object during GRO teardown can corrupt heap metadata or adjacent objects and be leveraged for control-flow hijacking, not merely a benign NULL check failure.\nA:H - A successful trigger causes a kernel NULL pointer dereference/oops in NAPI/softirq context (documented crash at vxlan_gro_prepare_receive), typically crashing or hanging the host and denying all services."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:46:49.365Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/9c58c729d32e7cea5772cc44929c6cd61e5a31cd"
        },
        {
          "url": "https://git.kernel.org/stable/c/f79c80f173fda9545b220c1f094b65fc06c252d0"
        },
        {
          "url": "https://git.kernel.org/stable/c/08f40c0d23c67c3aa4224c3311e134999c721fb4"
        },
        {
          "url": "https://git.kernel.org/stable/c/4a8cde6f7281ea2c4c290f9ad9923b3631defceb"
        },
        {
          "url": "https://git.kernel.org/stable/c/ef44dac2a37f86eeae6b88ed10a6d60b35387dfd"
        },
        {
          "url": "https://git.kernel.org/stable/c/30a45c0bffdd62350261e2f2689fdba426a33578"
        }
      ],
      "title": "vxlan: Fix potential null-ptr-deref in vxlan_gro_prepare_receive().",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74406",
    "datePublished": "2026-08-15T05:59:15.385Z",
    "dateReserved": "2026-08-15T05:44:03.892Z",
    "dateUpdated": "2026-08-17T05:46:49.365Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}