{
  "threat_severity" : "Moderate",
  "public_date" : "2026-04-03T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: net: usb: cdc_ncm: add ndpoffset to NDP16 nframes bounds check",
    "id" : "2454858",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2454858"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-1285",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnet: usb: cdc_ncm: add ndpoffset to NDP16 nframes bounds check\ncdc_ncm_rx_verify_ndp16() validates that the NDP header and its DPE\nentries fit within the skb. The first check correctly accounts for\nndpoffset:\nif ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len)\nbut the second check omits it:\nif ((sizeof(struct usb_cdc_ncm_ndp16) +\nret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len)\nThis validates the DPE array size against the total skb length as if\nthe NDP were at offset 0, rather than at ndpoffset. When the NDP is\nplaced near the end of the NTB (large wNdpIndex), the DPE entries can\nextend past the skb data buffer even though the check passes.\ncdc_ncm_rx_fixup() then reads out-of-bounds memory when iterating\nthe DPE array.\nAdd ndpoffset to the nframes bounds check and use struct_size_t() to\nexpress the NDP-plus-DPE-array size more clearly.", "A flaw was found in the Linux kernel's cdc_ncm module. An incorrect bounds check in the cdc_ncm_rx_verify_ndp16() function, responsible for validating Network Data Protocol (NDP) entries, allows Datagram Pointer Entries (DPE) to extend beyond the intended buffer. This can lead to an out-of-bounds read when cdc_ncm_rx_fixup() processes these entries, potentially resulting in information disclosure or a denial of service." ],
  "statement" : "This vulnerability affects systems using USB CDC NCM (Network Control Model) devices such as USB tethering adapters and mobile broadband modems. Exploitation requires either a malicious USB device or crafted network packets to a connected CDC NCM device. The out-of-bounds read could leak kernel memory or cause a crash.",
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-23448\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23448\nhttps://lore.kernel.org/linux-cve-announce/2026040315-CVE-2026-23448-1d79@gregkh/T" ],
  "name" : "CVE-2026-23448",
  "mitigation" : {
    "value" : "To mitigate this issue, prevent the cdc_ncm module from being loaded. See https://access.redhat.com/solutions/41278 for instructions. Note this will disable USB CDC NCM network devices.",
    "lang" : "en:us"
  },
  "csaw" : false
}