---
id: CVE-2026-98268
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  perf: Fix null pointer access in is_include_guest_event()

  A typical module unload occurring event when there is an active perf
  connection leads to freeing of the pmu p…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  perf: Fix null pointer access in is_include_guest_event()

  A typical module unload occurring event when there is an active perf
  connection leads to freeing of the pmu p…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= eff95e170275d9e80b968f335cd03d0ac250d2d1 <
    7fa9a465ae8f07c0e4685db6edb6a6f984dbd784
  - >-
    Linux >= eff95e170275d9e80b968f335cd03d0ac250d2d1 <
    88aed0422f39b22406f35f1e758cea25e7bbcfb5
  - Linux 7.0
published: '2026-10-06'
updated: '2026-10-06'
sourceUpdated: '2026-10-06T09:18:16.227'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98268'
references:
  - url: 'https://git.kernel.org/stable/c/7fa9a465ae8f07c0e4685db6edb6a6f984dbd784'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/88aed0422f39b22406f35f1e758cea25e7bbcfb5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-10-06T08:50:17.425Z'
---

## Overview

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

perf: Fix null pointer access in is_include_guest_event()

A typical module unload occurring event when there is an active perf
connection leads to freeing of the pmu pointer. The call log is something
like:
 ..
 __pmu_detach_event
 pmu_detach_event
 pmu_detach_events
 perf_pmu_unregister
 ..

__pmu_detach_event() sets event->pmu to null. When the perf connection
finally is closed, the following stack trace is observed:

 Oops: general protection fault, kernel NULL pointer dereference
 ...
 RIP: 0010:_free_event+0x3e/0x370
 ...
 Call Trace:
 ...
 perf_event_release_kernel+0x260/0x2d0
 perf_release+0x12/0x20

A call to mediated_pmu_unaccount_event() inside _free_event() is the root
cause of this crash. Adding a check inside is_include_guest_event() ensures
we don't accidentally access a null pmu ptr. In addition to this, we will
now call mediated_pmu_unaccount_event() before clearing the pmu ptr so that
nr_include_guest_events counts are maintained correctly.

## Remediation

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