Linux Kernel up to 6.1.27/6.2.14/6.3.1 mlx5e_clone_flow_attr_for_post_act use after free

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.27/6.2.14/6.3.1. It has been rated as critical. This issue affects the function mlx5e_clone_flow_attr_for_post_act. This manipulation causes use after free. This vulnerability is tracked as CVE-2023-54262. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.27/6.2.14/6.3.1. It has been declared as critical. Affected by this vulnerability is the function mlx5e_clone_flow_attr_for_post_act. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Don't clone flow post action attributes second time The code already clones post action attributes in mlx5e_clone_flow_attr_for_post_act(). Creating another copy in mlx5e_tc_post_act_add() is a erroneous leftover from original implementation. Instead, assign handle->attribute to post_attr provided by the caller. Note that cloning the attribute second time is not just wasteful but also causes issues like second copy not being properly updated in neigh update code which leads to following use-after-free: Feb 21 09:02:00 c-237-177-40-045 kernel: BUG: KASAN: use-after-free in mlx5_cmd_set_fte+0x200d/0x24c0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_report+0xbb/0x1a0 Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_save_stack+0x1e/0x40 Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_set_track+0x21/0x30 Feb 21 09:02:00 c-237-177-40-045 kernel: __kasan_kmalloc+0x7a/0x90 Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_save_stack+0x1e/0x40 Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_set_track+0x21/0x30 Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_save_free_info+0x2a/0x40 Feb 21 09:02:00 c-237-177-40-045 kernel: ____kasan_slab_free+0x11a/0x1b0 Feb 21 09:02:00 c-237-177-40-045 kernel: page dumped because: kasan: bad access detected Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5_core 0000:08:00.0: mlx5_cmd_out_err:803:(pid 8833): SET_FLOW_TABLE_ENTRY(0x936) op_mod(0x0) failed, status bad resource state(0x9), syndrome (0xf2ff71), err(-22) Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5_core 0000:08:00.0 enp8s0f0: Failed to add post action rule Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5_core 0000:08:00.0: mlx5e_tc_encap_flows_add:190:(pid 8833): Failed to update flow post acts, -22 Feb 21 09:02:00 c-237-177-40-045 kernel: Call Trace: Feb 21 09:02:00 c-237-177-40-045 kernel: <TASK> Feb 21 09:02:00 c-237-177-40-045 kernel: dump_stack_lvl+0x57/0x7d Feb 21 09:02:00 c-237-177-40-045 kernel: print_report+0x170/0x471 Feb 21 09:02:00 c-237-177-40-045 kernel: ? mlx5_cmd_set_fte+0x200d/0x24c0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_report+0xbb/0x1a0 Feb 21 09:02:00 c-237-177-40-045 kernel: ? mlx5_cmd_set_fte+0x200d/0x24c0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5_cmd_set_fte+0x200d/0x24c0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: ? __module_address.part.0+0x62/0x200 Feb 21 09:02:00 c-237-177-40-045 kernel: ? mlx5_cmd_stub_create_flow_table+0xd0/0xd0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: ? __raw_spin_lock_init+0x3b/0x110 Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5_cmd_create_fte+0x80/0xb0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: add_rule_fg+0xe80/0x19c0 [mlx5_core] -- Feb 21 09:02:00 c-237-177-40-045 kernel: Allocated by task 13476: Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_save_stack+0x1e/0x40 Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_set_track+0x21/0x30 Feb 21 09:02:00 c-237-177-40-045 kernel: __kasan_kmalloc+0x7a/0x90 Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5_packet_reformat_alloc+0x7b/0x230 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5e_tc_tun_create_header_ipv4+0x977/0xf10 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5e_attach_encap+0x15b4/0x1e10 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: post_process_attr+0x305/0xa30 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5e_tc_add_fdb_flow+0x4c0/0xcf0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: __mlx5e_add_fdb_flow+0x7cf/0xe90 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5e_configure_flower+0xcaa/0x4b90 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5e_rep_setup_tc_cls_flower+0x99/0x1b0 [mlx5_core] Feb 21 09:02:00 c-237-177-40-045 kernel: mlx5e_rep_setup_tc_cb+0x133/0x1e0 [mlx5_core] -- Feb 21 09:02:00 c-237-177-40-045 kernel: Freed by task 8833: Feb 21 09:02:00 c-237-177-40-045 kernel: kasan_save_s ---truncated---

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2023-54262 since 12/30/2025. The exploitation appears to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/27/2026).

The vulnerability scanner Nessus provides a plugin with the ID 281556 (Linux Distros Unpatched Vulnerability : CVE-2023-54262), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.28, 6.2.15 or 6.3.2 eliminates this vulnerability. Applying the patch c382b693ffcb1f1ebf60d76ab9dedfe9ea13eedf/8fd1dac646e6b08d03e3f1ad3c5b34255b1e08e8/2d57a514f9ab7d2d40f49b02d93edfcec8c78a9e/e9fce818fe003b6c527f25517b9ac08eb4661b5d 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 (281556) and CERT Bund (WID-SEC-2025-2941). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• IBM Power Hardware Management Console
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Open Source Linux Kernel
• RESF Rocky Linux
• IBM DataPower Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 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
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7
• 6.2.8
• 6.2.9
• 6.2.10
• 6.2.11
• 6.2.12
• 6.2.13
• 6.2.14
• 6.3.0
• 6.3.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

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Exploitinginfo

Threat Intelligenceinfo

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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