{
  "threat_severity" : "Moderate",
  "public_date" : "2026-02-14T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Linux kernel: Denial of Service in Bluetooth HCI UART driver via null pointer dereference",
    "id" : "2439882",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2439882"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.3",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L",
    "status" : "verified"
  },
  "cwe" : "CWE-476",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nBluetooth: hci_uart: fix null-ptr-deref in hci_uart_write_work\nhci_uart_set_proto() sets HCI_UART_PROTO_INIT before calling\nhci_uart_register_dev(), which calls proto->open() to initialize\nhu->priv. However, if a TTY write wakeup occurs during this window,\nhci_uart_tx_wakeup() may schedule write_work before hu->priv is\ninitialized, leading to a NULL pointer dereference in\nhci_uart_write_work() when proto->dequeue() accesses hu->priv.\nThe race condition is:\nCPU0                              CPU1\n----                              ----\nhci_uart_set_proto()\nset_bit(HCI_UART_PROTO_INIT)\nhci_uart_register_dev()\ntty write wakeup\nhci_uart_tty_wakeup()\nhci_uart_tx_wakeup()\nschedule_work(&hu->write_work)\nproto->open(hu)\n// initializes hu->priv\nhci_uart_write_work()\nhci_uart_dequeue()\nproto->dequeue(hu)\n// accesses hu->priv (NULL!)\nFix this by moving set_bit(HCI_UART_PROTO_INIT) after proto->open()\nsucceeds, ensuring hu->priv is initialized before any work can be\nscheduled.", "A flaw was found in the Linux kernel's Bluetooth HCI UART driver. A race condition exists where the `hci_uart_write_work()` function may attempt to access uninitialized private data if a TTY write wakeup occurs during the protocol initialization phase. This can lead to a NULL pointer dereference, potentially causing a system crash and resulting in a Denial of Service (DoS)." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20095",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.1",
    "package" : "kernel-0:6.12.0-124.8.1.el10_1"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20518",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.5.1.el9_7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20518",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.5.1.el9_7"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Under investigation",
    "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" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-23146\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23146\nhttps://lore.kernel.org/linux-cve-announce/2026021411-CVE-2026-23146-3658@gregkh/T" ],
  "name" : "CVE-2026-23146",
  "mitigation" : {
    "value" : "To mitigate this issue, prevent the `hci_uart` kernel module from loading. This can be achieved by creating a blacklist file for the module.\nCreate a file named `/etc/modprobe.d/blacklist-hci_uart.conf` with the following content:\n```\nblacklist hci_uart\ninstall hci_uart /bin/true\n```\nAfter creating the file, regenerate the initramfs to ensure the blacklist is applied during boot:\nFor RHEL 9 and 10:\n`sudo dracut -f -v`\nFor RHEL 6 ELS:\n`sudo dracut -f`\nA reboot is required for the changes to take effect. This mitigation will disable Bluetooth HCI UART functionality, which may impact systems relying on this driver for Bluetooth communication.",
    "lang" : "en:us"
  },
  "csaw" : false
}