{
  "threat_severity" : "Moderate",
  "public_date" : "2025-12-09T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_disconnect_{req,rsp}",
    "id" : "2420376",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2420376"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-416",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nBluetooth: L2CAP: Fix use-after-free in l2cap_disconnect_{req,rsp}\nSimilar to commit d0be8347c623 (\"Bluetooth: L2CAP: Fix use-after-free\ncaused by l2cap_chan_put\"), just use l2cap_chan_hold_unless_zero to\nprevent referencing a channel that is about to be destroyed." ],
  "statement" : "A race in the L2CAP disconnect request/response handlers could access a channel that is being destroyed, causing a use-after-free and kernel crash. The fix uses l2cap_chan_hold_unless_zero() and proper locking around channel deletion to avoid referencing freed objects. An adjacent attacker over Bluetooth can trigger this during disconnect handling on an active link. Likely only denial-of-service kind of attack possible, but cannot prove this.\nThe complexity of attack is high, because it requires a precise race condition between the local channel teardown (triggered by the kernel) and a crafted L2CAP_DisconnectReq or L2CAP_DisconnectRsp message sent by the remote peer at exactly the same time. The timing window is very narrow — the attacker must send or respond to the disconnect while the kernel is already in the process of releasing the l2cap_chan structure but before the reference count reaches zero. Achieving this reliably would require repeated connect/disconnect cycles or fuzzing at the signaling layer, making stable exploitation unlikely outside of a controlled test setup.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8.2 Advanced Update Support",
    "release_date" : "2026-02-26T00:00:00Z",
    "advisory" : "RHSA-2026:3388",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.2",
    "package" : "kernel-0:4.18.0-193.187.1.el8_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
    "release_date" : "2026-02-25T00:00:00Z",
    "advisory" : "RHSA-2026:3360",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.4",
    "package" : "kernel-0:4.18.0-305.186.1.el8_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
    "release_date" : "2026-02-25T00:00:00Z",
    "advisory" : "RHSA-2026:3360",
    "cpe" : "cpe:/o:redhat:rhel_eus_long_life:8.4",
    "package" : "kernel-0:4.18.0-305.186.1.el8_4"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Not 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" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2023-53827\nhttps://nvd.nist.gov/vuln/detail/CVE-2023-53827\nhttps://lore.kernel.org/linux-cve-announce/2025120952-CVE-2023-53827-b045@gregkh/T" ],
  "name" : "CVE-2023-53827",
  "csaw" : false
}