Linux Kernel up to 5.18.9 ad_clear_agg use after free

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.18.9. It has been classified as critical. Impacted is the function ad_clear_agg. Performing a manipulation results in use after free. This vulnerability is known as CVE-2022-49667. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 5.18.9. This affects the function ad_clear_agg. 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: net: bonding: fix use-after-free after 802.3ad slave unbind commit 0622cab0341c ("bonding: fix 802.3ad aggregator reselection"), resolve case, when there is several aggregation groups in the same bond. bond_3ad_unbind_slave will invalidate (clear) aggregator when __agg_active_ports return zero. So, ad_clear_agg can be executed even, when num_of_ports!=0. Than bond_3ad_unbind_slave can be executed again for, previously cleared aggregator. NOTE: at this time bond_3ad_unbind_slave will not update slave ports list, because lag_ports==NULL. So, here we got slave ports, pointing to freed aggregator memory. Fix with checking actual number of ports in group (as was before commit 0622cab0341c ("bonding: fix 802.3ad aggregator reselection") ), before ad_clear_agg(). The KASAN logs are as follows: [ 767.617392] ================================================================== [ 767.630776] BUG: KASAN: use-after-free in bond_3ad_state_machine_handler+0x13dc/0x1470 [ 767.638764] Read of size 2 at addr ffff00011ba9d430 by task kworker/u8:7/767 [ 767.647361] CPU: 3 PID: 767 Comm: kworker/u8:7 Tainted: G O 5.15.11 #15 [ 767.655329] Hardware name: DNI AmazonGo1 A7040 board (DT) [ 767.660760] Workqueue: lacp_1 bond_3ad_state_machine_handler [ 767.666468] Call trace: [ 767.668930] dump_backtrace+0x0/0x2d0 [ 767.672625] show_stack+0x24/0x30 [ 767.675965] dump_stack_lvl+0x68/0x84 [ 767.679659] print_address_description.constprop.0+0x74/0x2b8 [ 767.685451] kasan_report+0x1f0/0x260 [ 767.689148] __asan_load2+0x94/0xd0 [ 767.692667] bond_3ad_state_machine_handler+0x13dc/0x1470

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2022-49667 since 02/26/2025. The exploitability is told to be easy. 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 04/17/2025).

The vulnerability scanner Nessus provides a plugin with the ID 234545 (SUSE SLES12 Security Update : kernel (SUSE-SU-2025:1293-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.9.322, 4.14.287, 4.19.251, 5.4.204, 5.10.129, 5.15.53 or 5.18.10 eliminates this vulnerability. Applying the patch a853b7a3a9fd1d74a4ccdd9cd73512b7dace2f1e/b90ac60303063a43e17dd4aec159067599d255e6/f162f7c348fa2a5555bafdb5cc890b89b221e69c/893825289ba840afd86bfffcb6f7f363c73efff8/63b2fe509f69b90168a75e04e14573dccf7984e6/ef0af7d08d26c5333ff4944a559279464edf6f15/2765749def4765c5052a4c66445cf4c96fcccdbc/050133e1aa2cb49bb17be847d48a4431598ef562 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 vulnerability database at Tenable (234545). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.9.321
• 4.14.286
• 4.19.250
• 5.4.203
• 5.10.128
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.18.0
• 5.18.1
• 5.18.2
• 5.18.3
• 5.18.4
• 5.18.5
• 5.18.6
• 5.18.7
• 5.18.8
• 5.18.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Sourcesinfo

Entryinfo

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

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