SB20260918421 - Use-after-free in Linux kernel bluetooth



SB20260918421 - Use-after-free in Linux kernel bluetooth

Published: September 18, 2026

Security Bulletin ID SB20260918421
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Adjecent network
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Use-after-free (CVE-ID: CVE-2026-90256)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 6 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to use-after-free in the Bluetooth L2CAP l2cap_disconn_ind function when processing concurrent L2CAP connection deletion. A remote attacker can trigger concurrent L2CAP disconnection processing to cause a denial of service.


Remediation

Install update from vendor's website.