{
  "threat_severity" : "Moderate",
  "public_date" : "2025-09-05T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: vsock/virtio: Validate length in packet header before skb_put()",
    "id" : "2393507",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2393507"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.6",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-787",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nvsock/virtio: Validate length in packet header before skb_put()\nWhen receiving a vsock packet in the guest, only the virtqueue buffer\nsize is validated prior to virtio_vsock_skb_rx_put(). Unfortunately,\nvirtio_vsock_skb_rx_put() uses the length from the packet header as the\nlength argument to skb_put(), potentially resulting in SKB overflow if\nthe host has gone wonky.\nValidate the length as advertised by the packet header before calling\nvirtio_vsock_skb_rx_put()." ],
  "statement" : "A flaw in the virtio vsock receive path trusted the packet header’s len field and passed it to skb_put() without first ensuring it fit within the received buffer, enabling an out-of-bounds write if the host provides a malformed header (means attack from host to client). The patch validates the header-advertised payload length before calling virtio_vsock_skb_rx_put(). This is adjacent-vector and host-to-guest exploitable.\nThis vulnerability can only be exploited in environments where virtio-vsock is in use (i.e., when CONFIG_VIRTIO_VSOCKETS is enabled and guest-to-host communication via vsock is active).",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2025-10-27T00:00:00Z",
    "advisory" : "RHSA-2025:19106",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.0",
    "package" : "kernel-0:6.12.0-55.41.1.el10_0"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21118",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.1",
    "package" : "kernel-0:6.12.0-124.9.1.el10_1"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2025-11-17T00:00:00Z",
    "advisory" : "RHSA-2025:21397",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.84.1.rt7.425.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2025-11-17T00:00:00Z",
    "advisory" : "RHSA-2025:21398",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.84.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-10-27T00:00:00Z",
    "advisory" : "RHSA-2025:19105",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-570.58.1.el9_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21112",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.7.1.el9_7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-10-27T00:00:00Z",
    "advisory" : "RHSA-2025:19105",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-570.58.1.el9_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21112",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.7.1.el9_7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.4 Extended Update Support",
    "release_date" : "2025-10-27T00:00:00Z",
    "advisory" : "RHSA-2025:19104",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.4",
    "package" : "kernel-0:5.14.0-427.96.1.el9_4"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2025-39718\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-39718\nhttps://lore.kernel.org/linux-cve-announce/2025090551-CVE-2025-39718-2e2c@gregkh/T" ],
  "name" : "CVE-2025-39718",
  "mitigation" : {
    "value" : "To mitigate this issue, prevent module vmw_vsock_virtio_transport from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.",
    "lang" : "en:us"
  },
  "csaw" : false
}