bt: l2cap le coc: remote oob write via seg counter stored in net_buf user_data
CVE-2026-5068

7.6HIGH

Key Information:

Vendor

Zephyrproject-rtos

Status
Zephyr
Vendor
CVE Published:
9 June 2026

What is 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) 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.

Affected Version(s)

Zephyr 1.14.0 <= 4.3.0

References

https://github.com/zephyrproject-rtos/zephyr/security/adv...

CVSS V3.1

Score:
7.6
Severity:
HIGH
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.