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Fencer Vulns
high 7.8

CVE-2026-68394 json

Bluetooth: MGMT: revalidate LOAD_CONN_PARAM queued update

published 2026-08-10 2 mo ago modified 2026-10-19 20 d ago also EUVD-2026-55580

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 2%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: MGMT: revalidate LOAD_CONN_PARAM queued update

MGMT_OP_LOAD_CONN_PARAM queues conn_update_sync() when a single parameter update changes an existing LE central connection. The queued work currently stores a borrowed hci_conn_params entry from hdev->le_conn_params. A later LOAD_CONN_PARAM request can clear disabled parameters and free that entry before hci_cmd_sync_work() runs the queued callback.

Do not keep the borrowed hci_conn_params pointer in queued work. Queue the hci_conn instead and hold a reference until the queued callback completes. When the work runs, revalidate that the connection is still present, look up the current hci_conn_params entry, and cancel the update if userspace removed that entry while the work was pending.

Copy the interval values from the current params entry under hdev->lock, then drop the lock and keep using hci_le_conn_update_sync() to issue the update.

Validation reproduced this kernel report: BUG: KASAN: slab-use-after-free in conn_update_sync+0x2a/0xf0 [bluetooth] Read of size 1 at addr ffff88810c697126 by task kworker/u17:0/377 Workqueue: hci0 hci_cmd_sync_work [bluetooth]

Call Trace: <TASK> dump_stack_lvl+0x66/0xa0 print_report+0xce/0x5f0 kasan_report+0xe0/0x110 conn_update_sync+0x2a/0xf0 [bluetooth] hci_cmd_sync_work+0x187/0x210 [bluetooth] process_one_work+0x4fd/0xbc0 worker_thread+0x2d8/0x570 kthread+0x1ad/0x1f0 ret_from_fork+0x3c9/0x540 ret_from_fork_asm+0x1a/0x30

Allocated by task 466: hci_conn_params_add+0xa6/0x240 [bluetooth] load_conn_param+0x4e1/0x850 [bluetooth] hci_sock_sendmsg+0x96b/0xf80 [bluetooth]

Freed by task 474: kfree+0x313/0x590 hci_conn_params_clear_disabled+0x9b/0xc0 [bluetooth] load_conn_param+0x4bf/0x850 [bluetooth] hci_sock_sendmsg+0x96b/0xf80 [bluetooth]

Patch / fix

  • Linux Linux 6.12.101, 6.18.42, 7.1.6, 7.2
  • linux Debian 13 6.12.101-1
  • linux Debian 14 7.1.6-1
  • linux-6.12 Debian 12 6.12.101-1~deb12u1

debian advisories DEBIAN-CVE-2026-68394

  • linux Ubuntu 26.04 LTS 7.0.0-38.38
  • linux-aws Ubuntu 26.04 LTS 7.0.0-1014.14
  • linux-gcp Ubuntu 26.04 LTS 7.0.0-1014.14
  • linux-gke Ubuntu 26.04 LTS 7.0.0-1008.9
  • linux-ibm Ubuntu 26.04 LTS 7.0.0-1015.15
  • linux-azure Ubuntu 26.04 LTS 7.0.0-1017.17
  • linux-riscv Ubuntu 26.04 LTS 7.0.0-38.38.1
  • linux-oracle Ubuntu 26.04 LTS 7.0.0-1013.13

ubuntu advisories UBUNTU-CVE-2026-68394

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1
  • kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.81.1
  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.81.1
  • kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1
  • kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.81.1
  • kernel-zfcpdump SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1
  • kernel-obs-build SLE Module for Development Tools 15 SP7 6.4.0-150700.53.81.1
  • kernel-default-base SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1.150700.17.45.1

suse advisories SUSE-SU-2026:4254-1SUSE-SU-2026:23887-1SUSE-SU-2026:23902-1SUSE-SU-2026:23897-1SUSE-SU-2026:23881-1SUSE-SU-2026:4120-1

  • kernel-rt openSUSE Leap 16.0 6.12.0-160000.38.1
  • dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.38.1
  • kernel-64kb openSUSE Leap 16.0 6.12.0-160000.38.1
  • kernel-syms openSUSE Leap 16.0 6.12.0-160000.38.1
  • kernel-azure openSUSE Leap 16.0 6.12.0-160000.38.1
  • kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.38.1
  • kernel-source openSUSE Leap 16.0 6.12.0-160000.38.1
  • kernel-default openSUSE Leap 16.0 6.12.0-160000.38.1

opensuse advisories openSUSE-SU-2026:21910-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-68394 updated cvss 5.5

kernel: Bluetooth: MGMT: revalidate LOAD_CONN_PARAM queued update

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux 10 kernel 6.12.0-257.el10 Red Hat Enterprise Linux for NVIDIA 26 kernel 6.12.0-257.el10
    affected: no fix planned “Will not fix”
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +2 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +9 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +30 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-selftests-internal Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
23 d ago

Exploit prediction

0.13% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Linux Linux

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.