---
id: CVE-2026-90336
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  serial: core: clear freed pointers on uart_register_driver() failure

  uart_register_driver() leaves drv->state pointing to freed memory when
  tty_alloc_driver() fails
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  serial: core: clear freed pointers on uart_register_driver() failure

  uart_register_driver() leaves drv->state pointing to freed memory when
  tty_alloc_driver() fails. I…
severity: medium
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    06b376432974fe5f25f2843a8e8438c6a1cf3d50
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    61a2fb25551be0375bc16ef2a70c987dfca26183
  - Linux 2.6.12
published: '2026-09-17'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T11:18:01.297'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90336'
references:
  - url: 'https://git.kernel.org/stable/c/06b376432974fe5f25f2843a8e8438c6a1cf3d50'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/61a2fb25551be0375bc16ef2a70c987dfca26183'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ddf51d74ee9f9857c99477329d80408cedebda61'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a9c0ffe5930c97b352f32febfc59a6e6ae6772ee'
  - url: 'https://git.kernel.org/stable/c/802e2192a9d38027730c2869c67c9131b8c8fe9f'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90336.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-90336'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2536246'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-90336'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90336'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90336.mbox
  - url: 'https://kernelcve.org/list/?q=CVE-2026-90336'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00209
epssPercentile: 0.10971
ingestedAt: '2026-09-17T16:21:47.818Z'
cvss: 4.1
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe:
  - CWE-416
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

serial: core: clear freed pointers on uart_register_driver() failure

uart_register_driver() leaves drv->state pointing to freed memory when
tty_alloc_driver() fails. If tty_register_driver() fails, drv->tty_driver
also retains a pointer after its reference is dropped.

Drivers that use drv->state as an "already registered" flag can then skip
registration on the next probe and pass the freed state to
uart_add_one_port().

This issue was found with failslab on QEMU's raspi1ap board by
failing registration and binding the PL011 port again.

Clear both pointers on their failure paths, as uart_unregister_driver()
already does.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## 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-2026-90336.json)