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TI-2026-45509 Aliases CVE-2026-63944GHSA-q8jf-94w2-5pjv

Bluetooth: hci_sync: fix UAF in hci_le_create_cis_sync

Priority MEDIUM 40CWE-416Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: fix UAF in hci_le_create_cis_sync hci_le_create_cis_sync() dereferences conn->conn_timeout after releasing both rcu_read_lock() and hci_dev_lock(hdev). The conn pointer was obtained from an RCU-protected iteration over hdev->conn_hash.list and is not valid once these locks are dropped. A concurrent disconnect can free the hci_conn between the unlock and the dereference, causing a use-after-free read. The cancellation mechanism in hci_conn_del() cannot prevent this because hci_le_create_cis_pending() queues hci_create_cis_sync with data=NULL: hci_cmd_sync_queue(hdev, hci_create_cis_sync, NULL, NULL); While hci_conn_del() dequeues with data=conn: hci_cmd_sync_dequeue(hdev, NULL, conn, NULL); Since NULL != conn, the lookup in _hci_cmd_sync_lookup_entry() never matches, and the pending work item is not cancelled. Fix this by saving conn->conn_timeout into a local variable while the locks are still held, so the stale conn pointer is never dereferenced after unlock. This is the same class of bug as the one fixed by commit 035c25007c9e ("Bluetooth: hci_sync: Fix UAF on le_read_features_complete") which addressed the identical pattern in a different function. This vulnerability was identified using 0sec.ai, an open-source automated security auditing platform (https://github.com/0sec-labs).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00334 26th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.6.143, 6.12.93, 6.18.35 +2Red Hat: 2 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.4 and later6.6.143, 6.12.93, 6.18.35, 7.0.12, 7.1Patch availableCNA
  • Linux VendorLinux Affected 6.4 and later Fixed in 6.6.143, 6.12.93, 6.18.35, 7.0.12, 7.1 Patch available CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.4 to before 6.6.143; 6.7 to before 6.12.93; 6.13 to before 6.18.35; 6.19 to before 7.0.12VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*7.1 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*7.1 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*7.1 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*7.1 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*7.1 rc5VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.4 to before 6.6.143; 6.7 to before 6.12.93; 6.13 to before 6.18.35; 6.19 to before 7.0.12 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* Versions 7.1 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* Versions 7.1 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* Versions 7.1 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* Versions 7.1 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* Versions 7.1 rc5 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.143, 6.12.93, 6.18.35, 7.0.12, 7.1

Red Hat 2 advisories

  • RHSA-2026:67150 Released 2026-09-14 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.47.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.47.1.el9_8, kernel-64k-devel-5.14.0-687.47.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.47.1.el9_8, kernel-64k-5.14.0-687.47.1.el9_8, kernel-64k-core-5.14.0-687.47.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.47.1.el9_8, libperf-5.14.0-687.47.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.47.1.el9_8, kernel-rt-64k-5.14.0-687.47.1.el9_8, kernel-rt-64k-core-5.14.0-687.47.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.47.1.el9_8, kernel-rt-core-5.14.0-687.47.1.el9_8, kernel-rt-debug-5.14.0-687.47.1.el9_8 +9
  • RHSA-2026:65334 Released 2026-09-08 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.53.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.53.1.el10_2, kernel-64k-devel-6.12.0-211.53.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.53.1.el10_2, kernel-64k-6.12.0-211.53.1.el10_2, kernel-64k-core-6.12.0-211.53.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.53.1.el10_2, libperf-6.12.0-211.53.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.53.1.el10_2, kernel-rt-64k-6.12.0-211.53.1.el10_2, kernel-rt-64k-core-6.12.0-211.53.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.53.1.el10_2, kernel-rt-core-6.12.0-211.53.1.el10_2, kernel-rt-debug-6.12.0-211.53.1.el10_2 +9

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:65334
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:67150
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:65334
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:67150
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:65334
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:67150
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:65334
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:67150
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:65334
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:67150
Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-63944
  2. 2026-10-03 Alias added: GHSA-q8jf-94w2-5pjv
  3. 2026-10-13 Affected versions changed · Red Hat
  4. 2026-10-16 CISA SSVC decision points changed
  5. 2026-10-16 Priority changed: LOW → MEDIUM
  6. 2026-10-19 Weakness changed · CISA ADP
  7. 2026-10-29 Affected versions changed · Red Hat

References

Patch 5

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences