CVE-2026-5068
bt: l2cap le coc: remote oob write via seg counter stored in net_buf user_data
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.
INFO
Published Date :
June 9, 2026, 8:16 a.m.
Last Modified :
July 23, 2026, 8:10 a.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | e2e69745-5e70-4e92-8431-deb5529a81ad | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update Bluetooth host stack to patch L2CAP LE CoC SDU reassembly.
- Ensure RX pool user_data_size is adequate for segmentation counter.
- Test segmentation and buffer allocation logic carefully.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-5068.
| URL | Resource |
|---|---|
| https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-qrcq-hxwj-mqxm | Exploit Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-5068 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-5068
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-5068 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-5068 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 23, 2026
Action Type Old Value New Value Added Translation Title: Zephyr de zephyrproject-rtos, Description: Un par BLE remoto y no autenticado puede desencadenar una escritura fuera de límites de 2 bytes en el host Bluetooth durante el reensamblaje de SDU de L2CAP LE CoC. Cuando la aplicación habilita la segmentación (a través de chan_ops.alloc_buf) y el pool RX elegido tiene un user_data_size menor de 2 bytes, el contador de segmentación almacenado en el área user_data de net_buf se escribe fuera de límites en l2cap_chan_le_recv_seg (subsys/bluetooth/host/l2cap.c). Los efectos observados son una interrupción de AddressSanitizer y, sin ASan, corrupción de heap / error fatal. -
Initial Analysis by [email protected]
Jul. 08, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:* versions up to (including) 4.4.0 Added Reference Type Zephyr Project: https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-qrcq-hxwj-mqxm Types: Exploit, Patch, Vendor Advisory -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/zephyrproject-rtos/zephyr', 'vendor': 'zephyrproject-rtos', 'product': 'Zephyr', 'versions': [{'status': 'affected', 'version': '1.14.0', 'versionType': 'git', 'lessThanOrEqual': '4.3.0'}], 'packageName': 'Zephyr', 'defaultStatus': 'unaffected'}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-5068', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-09T13:10:35.371642Z'} -
New CVE Received by [email protected]
Jun. 09, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H Added CWE CWE-787 Added Reference https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-qrcq-hxwj-mqxm