---
id: CVE-2023-4133
title: 'Kernel: cxgb4: use-after-free in ch_flower_stats_cb()'
summary: >-
  A use-after-free vulnerability was found in the cxgb4 driver in the Linux
  kernel. The bug occurs when the cxgb4 device is detaching due to a possible
  rearming of the flower_stats_timer from the work queue. This flaw allows a
  local user t…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-416
vendor: Red Hat
product: kernel-rt
affected:
  - kernel-rt (all versions)
  - kernel (all versions)
  - kernel (all versions)
  - kernel (all versions)
  - kernel
  - kernel
  - kernel-rt
  - kernel-rt (all versions)
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2025-02-26T21:51:04.961885Z'
published: '2023-08-03'
updated: '2026-11-07'
sourceUpdated: '2026-11-07T11:31:56.937Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2023-4133'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2024:2394'
    label: 'RHSA-2024:2394'
  - url: 'https://access.redhat.com/errata/RHSA-2024:2950'
    label: 'RHSA-2024:2950'
  - url: 'https://access.redhat.com/errata/RHSA-2024:3138'
    label: 'RHSA-2024:3138'
  - url: 'https://access.redhat.com/security/cve/CVE-2023-4133'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2221702'
    label: RHBZ#2221702
tags:
  - cve.org
epss: 0.00228
epssPercentile: 0.13675
ingestedAt: '2026-11-07T12:16:41.118Z'
---

## Overview

A use-after-free vulnerability was found in the cxgb4 driver in the Linux kernel. The bug occurs when the cxgb4 device is detaching due to a possible rearming of the flower_stats_timer from the work queue. This flaw allows a local user to crash the system, causing a denial of service condition.

## Affected

- `kernel-rt (all versions)`
- `kernel (all versions)`
- `kernel (all versions)`
- `kernel (all versions)`
- `kernel`
- `kernel`
- `kernel-rt`
- `kernel-rt (all versions)`

## Remediation

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