SB20261022346 - Use-after-free in Linux kernel bluetooth rfcomm



SB20261022346 - Use-after-free in Linux kernel bluetooth rfcomm

Published: October 22, 2026

Security Bulletin ID SB20261022346
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Use-after-free (CVE-ID: CVE-2026-98739)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service through a kernel use-after-free.

The vulnerability exists due to a use-after-free in the Linux kernel Bluetooth RFCOMM TTY component when device installation and release concurrently manage the initial port reference for RFCOMM_RELEASE_ONHUP devices. A local user can trigger overlapping installation and release operations to cause both paths to drop the same initial reference, resulting in access to a freed port and potentially a kernel crash.


Remediation

Install update from vendor's website.