Local system crash via Bluetooth teardown timer race
Published Aug 15, 2026 · Updated Aug 15, 2026
Use-after-free in affected Linux kernel Bluetooth core releases allows local users to crash systems during HCI device teardown. hci_unregister_dev() frees hci_dev without synchronously disabling cmd_timer and ncmd_timer, so a concurrent timeout callback dereferences freed state, including hdev->reset. A low-privileged local user must win the race during Bluetooth device removal; the documented consequence is a kernel crash.
Summary
What happened
Use-after-free in affected Linux kernel Bluetooth core releases allows local users to crash systems during HCI device teardown. hci_unregister_dev() frees hci_dev without synchronously disabling cmd_timer and ncmd_timer, so a concurrent timeout callback dereferences freed state, including hdev->reset. A low-privileged local user must win the race during Bluetooth device removal; the documented consequence is a kernel crash.
The record
- CVE
- CVE-2026-74302
- Published
- Aug 15, 2026
- Updated
- Aug 15, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 15, 2026CVE publishedPublication date reported by the CVE source.
- Aug 15, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0d151a103775dd9645c78c97f77d6e2a5298d913 <48c7ad6afcc58c2cda11fed39791708103b6a644
- Affected versionversion=0d151a103775dd9645c78c97f77d6e2a5298d913 <5edcc018fa6e80b2c478454a4a8229c23d67c181
- Affected versionversion=0d151a103775dd9645c78c97f77d6e2a5298d913 <672d52d9412252e61b8de8d773ccdf5a277cf540
- Affected versionversion=0d151a103775dd9645c78c97f77d6e2a5298d913 <a0fd1086a57b982f8c24ae4ab165c2af39fe1735
- Affected versionversion=3f939bd73fed12dddc2a32a76116c19ca47c7678
- Affected versionversion=4.19.319 <4.20
- Affected versionversion=48542881997e17b49dc16b93fe910e0cfcf7a9f9
- Affected versionversion=5.10.223 <5.11
- Affected versionversion=5.15.164 <5.16
- Affected versionversion=5.4.281 <5.5
- Affected versionversion=6.10
- Affected versionversion=6.1.101 <6.2
- Affected versionversion=6.6.42 <6.7
- Affected versionversion=6.9.11 <6.10
- Affected versionversion=96600c2e5ee8213dbab5df1617293d8e847bb4fa
- Affected versionversion=9cfc84b1d464cc024286f42a090718f9067b80ed
- Affected versionversion=d2ce562a5aff1dcd0c50d9808ea825ef90da909f
- Affected versionversion=d6cbce18370641a21dd889e8613d8153df15eb39
- Affected versionversion=ddeda6ca5f218b668b560d90fc31ae469adbfd92
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo