---
id: CVE-2024-46786
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fscache: delete fscache_cookie_lru_timer when fscache exits to avoid UAF

  The fscache_cookie_lru_timer is initialized when the fscache module
  is inserted, but is not de…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fscache: delete fscache_cookie_lru_timer when fscache exits to avoid UAF

  The fscache_cookie_lru_timer is initialized when the fscache module
  is inserted, but is not de…
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 >= 5.17, < 6.1.160'
  - 'linux_kernel >= 6.2, < 6.6.51'
  - 'linux_kernel >= 6.7, < 6.10.10'
  - linux_kernel = 6.11
patched:
  - linux_kernel 6.10.10
published: '2024-09-18'
updated: '2026-07-14'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2024-46786'
references:
  - url: 'https://git.kernel.org/stable/c/0a11262549ac2ac6fb98c7cd40a67136817e5a52'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/72a6e22c604c95ddb3b10b5d3bb85b6ff4dbc34f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c1fc36d5470335546c45799d94d7bb2cbc09e8b7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e0d724932ad12e3528f4ce97fc0f6078d0cce4bc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00226
epssPercentile: 0.11785
ingestedAt: '2026-07-14T13:36:54.539Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2024-09-29T14:29:09.431104Z'
---

## Overview

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

fscache: delete fscache_cookie_lru_timer when fscache exits to avoid UAF

The fscache_cookie_lru_timer is initialized when the fscache module
is inserted, but is not deleted when the fscache module is removed.
If timer_reduce() is called before removing the fscache module,
the fscache_cookie_lru_timer will be added to the timer list of
the current cpu. Afterwards, a use-after-free will be triggered
in the softIRQ after removing the fscache module, as follows:

==================================================================
BUG: unable to handle page fault for address: fffffbfff803c9e9
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 21ffea067 P4D 21ffea067 PUD 21ffe6067 PMD 110a7c067 PTE 0
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G W 6.11.0-rc3 #855
Tainted: [W]=WARN
RIP: 0010:__run_timer_base.part.0+0x254/0x8a0
Call Trace:
 <IRQ>
 tmigr_handle_remote_up+0x627/0x810
 __walk_groups.isra.0+0x47/0x140
 tmigr_handle_remote+0x1fa/0x2f0
 handle_softirqs+0x180/0x590
 irq_exit_rcu+0x84/0xb0
 sysvec_apic_timer_interrupt+0x6e/0x90
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:default_idle+0xf/0x20
 default_idle_call+0x38/0x60
 do_idle+0x2b5/0x300
 cpu_startup_entry+0x54/0x60
 start_secondary+0x20d/0x280
 common_startup_64+0x13e/0x148
 </TASK>
Modules linked in: [last unloaded: netfs]
==================================================================

Therefore delete fscache_cookie_lru_timer when removing the fscahe module.

## Affected

- `linux_kernel >= 5.17, < 6.1.160`
- `linux_kernel >= 6.2, < 6.6.51`
- `linux_kernel >= 6.7, < 6.10.10`
- `linux_kernel = 6.11`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.10.10`