{
  "threat_severity" : "Moderate",
  "public_date" : "2026-05-01T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Bluetooth: hci_sync: fix stack buffer overflow in hci_le_big_create_sync",
    "id" : "2464502",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2464502"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.0",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-787",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nBluetooth: hci_sync: fix stack buffer overflow in hci_le_big_create_sync\nhci_le_big_create_sync() uses DEFINE_FLEX to allocate a\nstruct hci_cp_le_big_create_sync on the stack with room for 0x11 (17)\nBIS entries.  However, conn->num_bis can hold up to HCI_MAX_ISO_BIS (31)\nentries — validated against ISO_MAX_NUM_BIS (0x1f) in the caller\nhci_conn_big_create_sync().  When conn->num_bis is between 18 and 31,\nthe memcpy that copies conn->bis into cp->bis writes up to 14 bytes\npast the stack buffer, corrupting adjacent stack memory.\nThis is trivially reproducible: binding an ISO socket with\nbc_num_bis = ISO_MAX_NUM_BIS (31) and calling listen() will\neventually trigger hci_le_big_create_sync() from the HCI command\nsync worker, causing a KASAN-detectable stack-out-of-bounds write:\nBUG: KASAN: stack-out-of-bounds in hci_le_big_create_sync+0x256/0x3b0\nWrite of size 31 at addr ffffc90000487b48 by task kworker/u9:0/71\nFix this by changing the DEFINE_FLEX count from the incorrect 0x11 to\nHCI_MAX_ISO_BIS, which matches the maximum number of BIS entries that\nconn->bis can actually carry.", "A flaw was found in the Linux kernel's Bluetooth Host Controller Interface (HCI) synchronization. A local user could trigger a stack buffer overflow by binding a specific type of Bluetooth socket with an excessive number of Bluetooth Isochronous Stream (BIS) entries. This memory corruption can lead to a system crash, resulting in a denial of service." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2026-06-20T00:00:00Z",
    "advisory" : "RHSA-2026:27288",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.2",
    "package" : "kernel-0:6.12.0-211.26.1.el10_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-06-22T00:00:00Z",
    "advisory" : "RHSA-2026:27789",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.17.1.el9_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-06-22T00:00:00Z",
    "advisory" : "RHSA-2026:27789",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.17.1.el9_8"
  } ],
  "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 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "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-2026-31772\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31772\nhttps://lore.kernel.org/linux-cve-announce/2026050149-CVE-2026-31772-2024@gregkh/T" ],
  "name" : "CVE-2026-31772",
  "csaw" : false
}