Linux Kernel up to 6.4.6 bcm_proc_show use after free

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.4.6. It has been rated as critical. This vulnerability affects the function bcm_proc_show. Performing a manipulation results in use after free. This vulnerability is reported as CVE-2023-52922. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.4.6. It has been classified as critical. This affects the function bcm_proc_show. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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: 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.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2023-52922 since 08/21/2024. The exploitability is told to be difficult. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/22/2025).

The vulnerability scanner Nessus provides a plugin with the ID 214781 (SUSE SLES12 Security Update : kernel (SUSE-SU-2025:0236-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.123, 6.1.42 or 6.4.7 eliminates this vulnerability. Applying the patch 11b8e27ed448/9b58d36d0c1e/9533dbfac0ff/cf254b4f68e4/3c3941bb1eb5/995f47d76647/dfd0aa26e9a0/55c3b96074f3 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (214781) and CERT Bund (WID-SEC-2024-3565). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Open Source Linux Kernel
• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• Dell NetWorker
• Dell Avamar
• Red Hat OpenShift
• IBM QRadar SIEM

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.14.321
• 4.19.290
• 5.4.250
• 5.10.187
• 5.15.122
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.1.31
• 6.1.32
• 6.1.33
• 6.1.34
• 6.1.35
• 6.1.36
• 6.1.37
• 6.1.38
• 6.1.39
• 6.1.40
• 6.1.41
• 6.4.0
• 6.4.1
• 6.4.2
• 6.4.3
• 6.4.4
• 6.4.5
• 6.4.6

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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