CVE-2026-5068: Out-of-bounds Write in zephyrproject-rtos Zephyr
CVE-2026-5068 is a high-severity vulnerability in the Zephyr RTOS Bluetooth host stack. It allows a remote, unauthenticated BLE peer to trigger a 2-byte out-of-bounds write during L2CAP LE CoC SDU reassembly when segmentation is enabled and the RX pool's user_data_size is smaller than 2 bytes. This can lead to heap corruption or fatal errors, including AddressSanitizer aborts.
AI Analysis
Technical Summary
This vulnerability arises from an out-of-bounds write in the Bluetooth host's L2CAP LE CoC SDU reassembly code (l2cap_chan_le_recv_seg). When segmentation is enabled via chan_ops.alloc_buf and the RX pool's user_data_size is less than 2 bytes, the segmentation counter is written beyond the allocated buffer boundary. This flaw can be triggered remotely by an unauthenticated BLE peer, potentially causing heap corruption or application crashes.
Potential Impact
An attacker with remote BLE access can cause memory corruption leading to application crashes or fatal errors. The vulnerability impacts confidentiality, integrity, and availability with low confidentiality and integrity impact but high availability impact as per the CVSS vector. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid enabling segmentation with RX pools that have user_data_size smaller than 2 bytes. Monitor vendor channels for official patches or workarounds.
CVE-2026-5068: Out-of-bounds Write in zephyrproject-rtos Zephyr
Description
CVE-2026-5068 is a high-severity vulnerability in the Zephyr RTOS Bluetooth host stack. It allows a remote, unauthenticated BLE peer to trigger a 2-byte out-of-bounds write during L2CAP LE CoC SDU reassembly when segmentation is enabled and the RX pool's user_data_size is smaller than 2 bytes. This can lead to heap corruption or fatal errors, including AddressSanitizer aborts.
CVSS v3.1
Score 7.6high
Affected software
pkg:github/zephyrproject-rtos/zephyrRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability arises from an out-of-bounds write in the Bluetooth host's L2CAP LE CoC SDU reassembly code (l2cap_chan_le_recv_seg). When segmentation is enabled via chan_ops.alloc_buf and the RX pool's user_data_size is less than 2 bytes, the segmentation counter is written beyond the allocated buffer boundary. This flaw can be triggered remotely by an unauthenticated BLE peer, potentially causing heap corruption or application crashes.
Potential Impact
An attacker with remote BLE access can cause memory corruption leading to application crashes or fatal errors. The vulnerability impacts confidentiality, integrity, and availability with low confidentiality and integrity impact but high availability impact as per the CVSS vector. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid enabling segmentation with RX pools that have user_data_size smaller than 2 bytes. Monitor vendor channels for official patches or workarounds.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- zephyr
- Date Reserved
- 2026-03-27T22:48:19.869Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a27c1d4e29bf47b506900a0
Added to database: 06/09/2026, 07:33:40 UTC
Last enriched: 06/16/2026, 08:47:57 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 65
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