Read the docs
TI-2026-04423 Aliases CVE-2026-5068

bt: l2cap le coc: remote oob write via seg counter stored in net_buf user_data

Priority LOW 38CWE-787Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00452 39th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

No affected products listed by the sources yet.

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*up to 4.4.0Vulnerablezephyrproject
  • cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:* Versions up to 4.4.0 Vulnerable ·zephyrproject

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    zephyrproject-rtos Zephyr 4.3.1

    2 records Highest priority Priority HIGH 1 HIGH, 1 LOW

    Other records, highest priority first

    • TI-2026-04422 Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-KeyPriority HIGH 82
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-5068
  2. 2026-10-16 Fix available: [email protected] · CNA

References

Exploit 1

  • TI-2026-04422 Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key CVSS 3.1CRITICAL 9.8
  • TI-2026-01361 dns: memory‑safety issue in the DNS name parser CVSS 3.1CRITICAL 9.8
  • TI-2026-09174 Unterminated URI buffer causes out-of-bounds read in LwM2M firmware pull (Package URI) CVSS 3.1CRITICAL 9.1
  • TI-2026-09168 Stack buffer overflow in `net_ipaddr_parse()` IPv4 address-with-port parsing in `subsys/net/ip/utils.c` CVSS 3.1CRITICAL 9.8
  • TI-2024-09625 net: lib: http_server: Buffer Under-read CVSS 3.1HIGH 8.6
  • TI-2021-02863 Usb bluetooth device ACL read cb buffer overflow CVSS 3.1CRITICAL 9.6
See all 196 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences