CVE-2023-52922

Published Nov 28, 2024

Last updated a year ago

CVSS high 7.8
Linux Kernel

Overview

AI description

Automated description summarized from trusted sources.

CVE-2023-52922 is a use-after-free (UAF) vulnerability found in the Linux kernel's CAN (Controller Area Network) broadcast manager (BCM) protocol implementation. Specifically, the vulnerability lies within the `bcm_proc_show()` function, where `bcm_op` is freed before the procfs entry is removed in `bcm_release()`. This can lead to the reading of freed memory. This vulnerability occurs due to a race condition in the CAN BCM implementation. When `bcm_proc_show()` attempts to access memory that has already been freed, a use-after-free scenario arises. This was detected using the Kernel Address Sanitizer (KASAN). The vulnerability has been addressed by modifying the order of operations in `bcm_release()` to ensure the procfs entry is removed before freeing `bcm_op`.

Description
In the Linux kernel, the following vulnerability has been resolved: can: bcm: Fix UAF in bcm_proc_show() BUG: KASAN: slab-use-after-free in bcm_proc_show+0x969/0xa80 Read of size 8 at addr ffff888155846230 by task cat/7862 CPU: 1 PID: 7862 Comm: cat Not tainted 6.5.0-rc1-00153-gc8746099c197 #230 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0xd5/0x150 print_report+0xc1/0x5e0 kasan_report+0xba/0xf0 bcm_proc_show+0x969/0xa80 seq_read_iter+0x4f6/0x1260 seq_read+0x165/0x210 proc_reg_read+0x227/0x300 vfs_read+0x1d5/0x8d0 ksys_read+0x11e/0x240 do_syscall_64+0x35/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd Allocated by task 7846: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 __kasan_kmalloc+0x9e/0xa0 bcm_sendmsg+0x264b/0x44e0 sock_sendmsg+0xda/0x180 ____sys_sendmsg+0x735/0x920 ___sys_sendmsg+0x11d/0x1b0 __sys_sendmsg+0xfa/0x1d0 do_syscall_64+0x35/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 7846: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x27/0x40 ____kasan_slab_free+0x161/0x1c0 slab_free_freelist_hook+0x119/0x220 __kmem_cache_free+0xb4/0x2e0 rcu_core+0x809/0x1bd0 bcm_op is freed before procfs entry be removed in bcm_release(), this lead to bcm_proc_show() may read the freed bcm_op.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-416

Social media

Hype score
Not currently trending

  1. #exploit #Kernel_Security 1. CVE-2025-22056: The tragedy of Netfilter Tunnel - https://t.co/YsrT8m5Ksx 2. CVE-2023-52922: UaF in CAN BCM subsystem leading to information disclosure - https://t.co/70ehMbC8OP 3. CVE-2025-22037: Remote NULL Deref in Linux KSMBD -

    @ksg93rd

    5 Jul 2025

    2142 Impressions

    12 Retweets

    49 Likes

    24 Bookmarks

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  2. We wrote a blog post about a Linux kernel vulnerability we reported to Red Hat in July 2024. The vulnerability had been fixed upstream a year before, but Red Hat and derivatives distributions didn't backport the patch. It was assigned the CVE-2023-52922 after we reported it.

    @alleleintel

    9 Jun 2025

    4788 Impressions

    8 Retweets

    26 Likes

    4 Bookmarks

    1 Reply

    1 Quote

  3. CVE-2023-52922 Use-After-Free Vulnerability Rectified in Linux Kernel's CAN BCM A problem in the Linux kernel has now been fixed. There was a vulnerability called "can: bcm: Fix UAF in bcm_proc_show()." It involv... https://t.co/W4jIA2UHZ2

    @VulmonFeeds

    29 Nov 2024

    67 Impressions

    0 Retweets

    1 Like

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  4. CVE-2023-52922 In the Linux kernel, the following vulnerability has been resolved: can: bcm: Fix UAF in bcm_proc_show() BUG: KASAN: slab-use-after-free in bcm_proc_show+0x969/0xa8… https://t.co/QgrGuCbVex

    @CVEnew

    28 Nov 2024

    428 Impressions

    0 Retweets

    1 Like

    0 Bookmarks

    0 Replies

    0 Quotes

Configurations

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References

Sources include official advisories and independent security research.