zephyrproject-rtos Zephyr up to 4.3.0 l2cap.c l2cap_chan_le_recv_seg out-of-bounds write

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.9$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in zephyrproject-rtos Zephyr up to 4.3.0. Affected by this vulnerability is the function l2cap_chan_le_recv_seg of the file subsys/bluetooth/host/l2cap.c. The manipulation results in out-of-bounds write. This vulnerability was named CVE-2026-5068. The attack needs to be approached within the local network. There is no available exploit.

Detailsinfo

A vulnerability classified as critical has been found in zephyrproject-rtos Zephyr up to 4.3.0. Affected is the function l2cap_chan_le_recv_seg of the file subsys/bluetooth/host/l2cap.c. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-5068 since 03/27/2026. The exploitability is told to be easy. The attack can only be done within the local network. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/09/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.9

VulDB Base Score: 6.3
VulDB Temp Score: 6.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.6
CNA Vector (zephyr): 🔒

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/27/2026 CVE reserved
06/09/2026 +73 days Advisory disclosed
06/09/2026 +0 days VulDB entry created
06/09/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-5068 (🔒)
GCVE (CVE): GCVE-0-2026-5068
GCVE (VulDB): GCVE-100-369468

Entryinfo

Created: 06/09/2026 12:15
Changes: 06/09/2026 12:15 (64)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to know what is going to be exploited?

We predict KEV entries!