{
  "threat_severity" : "Moderate",
  "public_date" : "2026-04-24T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: HID: core: clamp report_size in s32ton() to avoid undefined shift",
    "id" : "2461477",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2461477"
  },
  "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-1335",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nHID: core: clamp report_size in s32ton() to avoid undefined shift\ns32ton() shifts by n-1 where n is the field's report_size, a value that\ncomes directly from a HID device.  The HID parser bounds report_size\nonly to <= 256, so a broken HID device can supply a report descriptor\nwith a wide field that triggers shift exponents up to 256 on a 32-bit\ntype when an output report is built via hid_output_field() or\nhid_set_field().\nCommit ec61b41918587 (\"HID: core: fix shift-out-of-bounds in\nhid_report_raw_event\") added the same n > 32 clamp to the function\nsnto32(), but s32ton() was never given the same fix as I guess syzbot\nhadn't figured out how to fuzz a device the same way.\nFix this up by just clamping the max value of n, just like snto32()\ndoes.", "A flaw was found in the Linux kernel's Human Interface Device (HID) core. A malicious or malformed HID device could provide a specially crafted report descriptor with an overly large `report_size` value. This could lead to an undefined shift operation within the `s32ton()` function when processing output reports. This vulnerability may result in system instability or a denial of service (DoS)." ],
  "statement" : "HID `s32ton()` now clamps `report_size` so pathological descriptors cannot provoke undefined left-shift behavior. Red Hat treats this as local USB/HID attack surface hardening. Core HID is not practically unloadable; patch kernels.",
  "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" : "Not affected",
    "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-2026-31624\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31624\nhttps://lore.kernel.org/linux-cve-announce/2026042426-CVE-2026-31624-e19a@gregkh/T" ],
  "name" : "CVE-2026-31624",
  "csaw" : false
}