HIGH · 7.6

CVE-2026-5068

A remote, unauthenticated BLE peer can trigger a 2-byte out-of-bounds write in the Bluetooth host during L2CAP LE CoC SDU reassembly. When the application enables segmentation (via chan_ops.alloc_buf)...

Vulnerability Description

A remote, unauthenticated BLE peer can trigger a 2-byte out-of-bounds write in the Bluetooth host during L2CAP LE CoC SDU reassembly. When the application enables segmentation (via chan_ops.alloc_buf) and the chosen RX pool has a user_data_size smaller than 2 bytes, the segmentation counter stored in the net_buf user_data area is written out of bounds in l2cap_chan_le_recv_seg (subsys/bluetooth/host/l2cap.c). The observed effects are an AddressSanitizer abort and, without ASan, heap corruption / fatal error.

CVSS Score

7.6

HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
Attack Vector
ADJACENT_NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
HIGH

Affected Products

VendorProductVersions
ZephyrprojectZephyr<= 4.4.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-5068?

CVE-2026-5068 is a vulnerability with a CVSS score of 7.6 (HIGH). A remote, unauthenticated BLE peer can trigger a 2-byte out-of-bounds write in the Bluetooth host during L2CAP LE CoC SDU reassembly. When the application enables segmentation (via chan_ops.alloc_buf)...

How severe is CVE-2026-5068?

CVE-2026-5068 has been rated HIGH with a CVSS base score of 7.6/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-5068?

Check the references section above for vendor advisories and patch information. Affected products include: Zephyrproject Zephyr.