Device crash via transmit-buffer double-free
Published Aug 11, 2026 · Updated Aug 11, 2026
Double-free in the Realtek BEE Bluetooth HCI driver in Zephyr RTOS 4.4.0 through 4.4.1 allows physically proximate attackers to crash devices. The bt_hci_bee_send() error path unrefs a transmit net_buf that the host still owns, so host cleanup frees it again and later logging reads freed memory. Exploitation requires a build using this driver and Bluetooth traffic that induces allocation or controller-send failure; pool corruption primarily crashes the device.
Summary
What happened
Double-free in the Realtek BEE Bluetooth HCI driver in Zephyr RTOS 4.4.0 through 4.4.1 allows physically proximate attackers to crash devices. The bt_hci_bee_send() error path unrefs a transmit net_buf that the host still owns, so host cleanup frees it again and later logging reads freed memory. Exploitation requires a build using this driver and Bluetooth traffic that induces allocation or controller-send failure; pool corruption primarily crashes the device.
The record
- CVE
- CVE-2026-11894
- Published
- Aug 11, 2026
- Updated
- Aug 11, 2026
- Vendor
- Zephyr Project
- Product
- Zephyr RTOS
- Classifications
- CWE-415, CWE-416, T1499.004
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 11, 2026CVE publishedPublication date reported by the CVE source.
- Aug 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=4.4.0 <4.4.2
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
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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