{
  "threat_severity" : "Moderate",
  "public_date" : "2026-05-01T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Bluetooth: SCO: fix race conditions in sco_sock_connect()",
    "id" : "2464496",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2464496"
  },
  "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" : "draft"
  },
  "cwe" : "CWE-821",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nBluetooth: SCO: fix race conditions in sco_sock_connect()\nsco_sock_connect() checks sk_state and sk_type without holding\nthe socket lock. Two concurrent connect() syscalls on the same\nsocket can both pass the check and enter sco_connect(), leading\nto use-after-free.\nThe buggy scenario involves three participants and was confirmed\nwith additional logging instrumentation:\nThread A (connect):    HCI disconnect:      Thread B (connect):\nsco_sock_connect(sk)                        sco_sock_connect(sk)\nsk_state==BT_OPEN                           sk_state==BT_OPEN\n(pass, no lock)                             (pass, no lock)\nsco_connect(sk):                            sco_connect(sk):\nhci_dev_lock                                hci_dev_lock\nhci_connect_sco                               <- blocked\n-> hcon1\nsco_conn_add->conn1\nlock_sock(sk)\nsco_chan_add:\nconn1->sk = sk\nsk->conn = conn1\nsk_state=BT_CONNECT\nrelease_sock\nhci_dev_unlock\nhci_dev_lock\nsco_conn_del:\nlock_sock(sk)\nsco_chan_del:\nsk->conn=NULL\nconn1->sk=NULL\nsk_state=\nBT_CLOSED\nSOCK_ZAPPED\nrelease_sock\nhci_dev_unlock\n(unblocked)\nhci_connect_sco\n-> hcon2\nsco_conn_add\n-> conn2\nlock_sock(sk)\nsco_chan_add:\nsk->conn=conn2\nsk_state=\nBT_CONNECT\n// zombie sk!\nrelease_sock\nhci_dev_unlock\nThread B revives a BT_CLOSED + SOCK_ZAPPED socket back to\nBT_CONNECT. Subsequent cleanup triggers double sock_put() and\nuse-after-free. Meanwhile conn1 is leaked as it was orphaned\nwhen sco_conn_del() cleared the association.\nFix this by:\n- Moving lock_sock() before the sk_state/sk_type checks in\nsco_sock_connect() to serialize concurrent connect attempts\n- Fixing the sk_type != SOCK_SEQPACKET check to actually\nreturn the error instead of just assigning it\n- Adding a state re-check in sco_connect() after lock_sock()\nto catch state changes during the window between the locks\n- Adding sco_pi(sk)->conn check in sco_chan_add() to prevent\ndouble-attach of a socket to multiple connections\n- Adding hci_conn_drop() on sco_chan_add failure to prevent\nHCI connection leaks", "A flaw was found in the Linux kernel, specifically within its Bluetooth Synchronous Connection-Oriented (SCO) component. This vulnerability occurs due to race conditions when multiple connection attempts are made simultaneously on the same Bluetooth socket. This can lead to a use-after-free error, where the system attempts to use memory that has already been released. Exploitation of this flaw could result in system instability, causing the system to crash or become unresponsive, and potentially lead to a denial of service." ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Affected",
    "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" : "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",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "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-2026-43023\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-43023\nhttps://lore.kernel.org/linux-cve-announce/2026050158-CVE-2026-43023-19eb@gregkh/T" ],
  "name" : "CVE-2026-43023",
  "csaw" : false
}