---
id: CVE-2026-98753
title: >-
  kernel: tty: tty_port: restore TTY_IO_ERROR on activation failure
  (CVE-2026-98753)
summary: >-
  A flaw was found in the Linux kernel's TTY subsystem. A local user can cause a
  Denial of Service (DoS) by triggering a race condition during terminal device
  activation and hangup operations. When device activation fails, the kernel
  fails t…
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-366
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 7
  - enterprise_linux 8
  - enterprise_linux 9
  - openshift_container_platform 4
published: '2026-10-18'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T03:43:05+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98753.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98753.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98753'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2555045'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98753'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98753'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98753.mbox
  - url: 'https://git.kernel.org/stable/c/16032c980d8f71642fcdc99309c571df3fcf3328'
  - url: 'https://git.kernel.org/stable/c/34d4f67472ef7a744970b772a8565ddc727788e2'
  - url: 'https://git.kernel.org/stable/c/7021acc84c2e0add77a1a33152e3a1e428fdbfdb'
  - url: 'https://git.kernel.org/stable/c/6388409b711eb91b14fa075a4d861ccc4df1cfe7'
  - url: 'https://git.kernel.org/stable/c/56964f6a31238fb41d5830bb42520c5b10ff7d8f'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00168
epssPercentile: 0.05987
ingestedAt: '2026-10-18T16:47:32.499Z'
---

## Overview

A flaw was found in the Linux kernel's TTY subsystem. A local user can cause a Denial of Service (DoS) by triggering a race condition during terminal device activation and hangup operations. When device activation fails, the kernel fails to restore an error flag, allowing subsequent input/output operations on powered-down or deregistered ports. This improper access can trigger a null-pointer dereference or unclocked hardware access, resulting in a kernel crash.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98753.json)

**kernel: tty: tty_port: restore TTY_IO_ERROR on activation failure** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-23.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

No fix planned:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

Not affected:

- Red Hat Enterprise Linux 6

## Remediation

Fix deferred