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

Bluetooth: hci_sync: extend conn_hash lookup critical sections

Using RCU-protected pointers outside the critical sections without
refcount is incorrect and may result to UAF.

Extend critical section to cover both hci_conn_hash lookup and use of
the returned conn.

Add surrounding rcu_read_lock() also when return value is not used, in
preparation for RCU lockdep requirement to hci_lookup_le_connect().

This avoids concurrent deletion of the conn before we are done
dereferencing it.

Also, make sure to hold hdev->lock when accessing hdev->accept_list.
Published: 2026-08-10
Score: 8.8 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

In the Linux kernel Bluetooth subsystem, a race condition involves RCU‑protected pointers accessed outside their critical sections, resulting in a use‑after‑free of a connection structure. This flaw could allow an attacker to dereference freed memory, enabling execution of arbitrary code with kernel privileges or causing a kernel crash.

Affected Systems

All Linux kernels that include the default Bluetooth driver carry the risk; specific affected releases are not enumerated in the available data and should be patched once the fix is released.

Risk and Exploitability

The CVE has a CVSS score of 8.8 and an EPSS score of less than 1%, indicating high severity but low likelihood of exploitation. It is not listed in CISA’s KEV catalog, and the vulnerability involves a use‑after‑free due to race conditions in the Bluetooth subsystem. Although no public exploitation has been documented, an attacker could trigger the race by interacting with the Bluetooth stack, potentially leading to kernel privilege escalation or a crash. The exploit would require precise timing and user‑space control of the Bluetooth connection to create the concurrency condition.

Generated by OpenCVE AI on August 14, 2026 at 03:46 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Update the Linux kernel to the patched version that extends the critical sections around hci_conn_hash lookup and hci_lookup_le_connect.
  • If an immediate kernel update is not possible, disable the Bluetooth subsystem or unload its modules to prevent the UAF condition.
  • Apply the patch series referenced in commits 38326774df6198df0cc2744cc73bf77cb741c538, 83b7e67698d0b93f685875ce82c8d335436834f7, or d5efd6e4b8b0634af6843178fe1a7dd2b2178a3d to the source tree and recompile the kernel.

Generated by OpenCVE AI on August 14, 2026 at 03:46 UTC.

Tracking

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Advisories

No advisories yet.

History

Fri, 14 Aug 2026 02:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Thu, 13 Aug 2026 23:15:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}


Wed, 12 Aug 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-825
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Important


Mon, 10 Aug 2026 16:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Mon, 10 Aug 2026 12:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: extend conn_hash lookup critical sections Using RCU-protected pointers outside the critical sections without refcount is incorrect and may result to UAF. Extend critical section to cover both hci_conn_hash lookup and use of the returned conn. Add surrounding rcu_read_lock() also when return value is not used, in preparation for RCU lockdep requirement to hci_lookup_le_connect(). This avoids concurrent deletion of the conn before we are done dereferencing it. Also, make sure to hold hdev->lock when accessing hdev->accept_list.
Title Bluetooth: hci_sync: extend conn_hash lookup critical sections
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-17T05:04:41.234Z

Reserved: 2026-07-30T09:28:09.388Z

Link: CVE-2026-68393

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-10T13:20:32.663

Modified: 2026-08-17T06:17:47.983

Link: CVE-2026-68393

cve-icon Redhat

Severity : Important

Publid Date: 2026-08-10T12:04:12Z

Links: CVE-2026-68393 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-08-14T04:00:11Z

Weaknesses
  • CWE-825

    Expired Pointer Dereference