SB20261022458 - Use-after-free in Linux kernel tty vt driver

CSH
CYBERSECURITY HELP
Sign In REGISTER

Main Vulnerability Database SB20261022458

SB20261022458 - Use-after-free in Linux kernel tty vt driver

Published: October 22, 2026

Security Bulletin ID SB20261022458
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-2026-98840)

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 potentially cause a denial of service through a kernel use-after-free.

The vulnerability exists due to use-after-free in the Linux kernel's vcs_write() function when a copy failure exits the write loop without refreshing a virtual console pointer following concurrent console deallocation. A local user can perform virtual console writes that encounter a copy failure while racing with console deallocation to trigger a stale-pointer dereference in vcs_notifier() and potentially crash the kernel.


Remediation

Install update from vendor's website.

References