---
id: CVE-2023-6535
title: 'Kernel: null pointer dereference in nvmet_tcp_execute_request'
summary: >-
  A flaw was found in the Linux kernel's NVMe driver. This issue may allow an
  unauthenticated malicious actor to send a set of crafted TCP packages when
  using NVMe over TCP, leading the NVMe driver to a NULL pointer dereference in
  the NVMe…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-476
vendor: Red Hat
product: kernel-rt
affected:
  - kernel-rt (all versions)
  - kernel (all versions)
  - kernel (all versions)
  - kernel (all versions)
  - kernel (all versions)
  - kernel (all versions)
  - kernel (all versions)
  - kernel-rt (all versions)
  - kernel (all versions)
  - openshift-logging/cluster-logging-operator-bundle (all versions)
  - openshift-logging/cluster-logging-rhel9-operator (all versions)
  - openshift-logging/elasticsearch6-rhel9 (all versions)
  - openshift-logging/elasticsearch-operator-bundle (all versions)
  - openshift-logging/elasticsearch-proxy-rhel9 (all versions)
  - openshift-logging/elasticsearch-rhel9-operator (all versions)
  - openshift-logging/eventrouter-rhel9 (all versions)
  - openshift-logging/fluentd-rhel9 (all versions)
  - openshift-logging/log-file-metric-exporter-rhel9 (all versions)
  - openshift-logging/logging-curator5-rhel9 (all versions)
  - openshift-logging/logging-loki-rhel9 (all versions)
  - openshift-logging/logging-view-plugin-rhel9 (all versions)
  - openshift-logging/loki-operator-bundle (all versions)
  - openshift-logging/loki-rhel9-operator (all versions)
  - openshift-logging/lokistack-gateway-rhel9 (all versions)
  - openshift-logging/opa-openshift-rhel9 (all versions)
  - openshift-logging/vector-rhel9 (all versions)
  - kernel
  - kernel
  - kernel-rt
  - kernel-rt (all versions)
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2024-02-08T17:12:36.607009Z'
published: '2024-02-07'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T11:37:10.300Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2023-6535'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2024:0723'
    label: 'RHSA-2024:0723'
  - url: 'https://access.redhat.com/errata/RHSA-2024:0724'
    label: 'RHSA-2024:0724'
  - url: 'https://access.redhat.com/errata/RHSA-2024:0725'
    label: 'RHSA-2024:0725'
  - url: 'https://access.redhat.com/errata/RHSA-2024:0881'
    label: 'RHSA-2024:0881'
  - url: 'https://access.redhat.com/errata/RHSA-2024:0897'
    label: 'RHSA-2024:0897'
  - url: 'https://access.redhat.com/errata/RHSA-2024:1248'
    label: 'RHSA-2024:1248'
  - url: 'https://access.redhat.com/errata/RHSA-2024:2094'
    label: 'RHSA-2024:2094'
  - url: 'https://access.redhat.com/errata/RHSA-2024:3810'
    label: 'RHSA-2024:3810'
  - url: 'https://access.redhat.com/security/cve/CVE-2023-6535'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2254053'
    label: RHBZ#2254053
tags:
  - cve.org
epss: 0.01549
epssPercentile: 0.75146
ingestedAt: '2026-11-05T21:36:00.809Z'
---

## Overview

A flaw was found in the Linux kernel's NVMe driver. This issue may allow an unauthenticated malicious actor to send a set of crafted TCP packages when using NVMe over TCP, leading the NVMe driver to a NULL pointer dereference in the NVMe driver, causing kernel panic and a denial of service.

## Affected

- `kernel-rt (all versions)`
- `kernel (all versions)`
- `kernel (all versions)`
- `kernel (all versions)`
- `kernel (all versions)`
- `kernel (all versions)`
- `kernel (all versions)`
- `kernel-rt (all versions)`
- `kernel (all versions)`
- `openshift-logging/cluster-logging-operator-bundle (all versions)`
- `openshift-logging/cluster-logging-rhel9-operator (all versions)`
- `openshift-logging/elasticsearch6-rhel9 (all versions)`
- `openshift-logging/elasticsearch-operator-bundle (all versions)`
- `openshift-logging/elasticsearch-proxy-rhel9 (all versions)`
- `openshift-logging/elasticsearch-rhel9-operator (all versions)`
- `openshift-logging/eventrouter-rhel9 (all versions)`
- `openshift-logging/fluentd-rhel9 (all versions)`
- `openshift-logging/log-file-metric-exporter-rhel9 (all versions)`
- `openshift-logging/logging-curator5-rhel9 (all versions)`
- `openshift-logging/logging-loki-rhel9 (all versions)`
- `openshift-logging/logging-view-plugin-rhel9 (all versions)`
- `openshift-logging/loki-operator-bundle (all versions)`
- `openshift-logging/loki-rhel9-operator (all versions)`
- `openshift-logging/lokistack-gateway-rhel9 (all versions)`
- `openshift-logging/opa-openshift-rhel9 (all versions)`
- `openshift-logging/vector-rhel9 (all versions)`
- `kernel`
- `kernel`
- `kernel-rt`
- `kernel-rt (all versions)`

## Remediation

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

### Workarounds

To mitigate this issue, prevent module nvmet-tcp from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.