---
id: CVE-2026-64075
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fprobe: Fix unregister_fprobe() to wait for RCU grace period

  Commit 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
  changed fprobe to register struct…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fprobe: Fix unregister_fprobe() to wait for RCU grace period

  Commit 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
  changed fprobe to register struct…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 6.14, < 6.18.34'
  - 'linux_kernel >= 6.19, < 7.0.11'
  - linux_kernel = 7.1
patched:
  - linux_kernel 7.0.11
published: '2026-07-19'
updated: '2026-09-03'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64075'
references:
  - url: 'https://git.kernel.org/stable/c/56b4cfcf1518245493c60fd39c56978f508f1816'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/657b594b2084b39a4bc6d8493aa2140cb00cea49'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a4f6a9005ed6cfd360ef2520430927f05f92ffb0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00124
epssPercentile: 0.02439
ingestedAt: '2026-09-04T05:15:22.749Z'
---

## Overview

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

fprobe: Fix unregister_fprobe() to wait for RCU grace period

Commit 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
changed fprobe to register struct fprobe to an rcu-hlist, but it forgot
to wait for RCU GP. Thus there can be use-after-free if the fprobe is
released right after unregistering. This can be happened on fprobe
event and sample module code.

To fix this issue, add synchronize_rcu() in unregister_fprobe().

Note that BPF is OK because fprobe is used as a part of
bpf_kprobe_multi_link. This unregisters its fprobe in
bpf_kprobe_multi_link_release() and it is deallocated via
bpf_kprobe_multi_link_dealloc(), which is invoked from
bpf_link_defer_dealloc_rcu_gp() RCU callback.

For BPF, this also introduced unregister_fprobe_async() which does
NOT wait for RCU grace priod.

## Affected

- `linux_kernel >= 6.14, < 6.18.34`
- `linux_kernel >= 6.19, < 7.0.11`
- `linux_kernel = 7.1`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.11`