CVE-2026-53230

net/mlx5: Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list

Published Jun 25, 2026 CVSS 3.1 · 8.7 High EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

net/mlx5: Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list

mlx5_query_nic_vport_mac_list() sizes its firmware command buffer using
the PF's log_max_current_uc/mc_list capabilities. When querying a VF
vport with a larger configured max (via devlink), the firmware response
can overflow this buffer:

BUG: KASAN: slab-out-of-bounds in mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core]
Read of size 4 at addr ff1100013ffc8a12 by task kworker/u96:2/385

CPU: 12 UID: 0 PID: 385 Comm: kworker/u96:2 Not tainted 7.0.0-rc6+ #1 PREEMPT
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009)
Workqueue: mlx5_esw_wq esw_vport_change_handler [mlx5_core]
Call Trace:
<TASK>
dump_stack_lvl+0x69/0xa0
print_report+0x176/0x4e4
kasan_report+0xc8/0x100
mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core]
esw_update_vport_addr_list+0x2e3/0xda0 [mlx5_core]
esw_vport_change_handle_locked+0xa1f/0x1060 [mlx5_core]
esw_vport_change_handler+0x6a/0x90 [mlx5_core]
process_one_work+0x87f/0x15e0
worker_thread+0x62b/0x1020
kthread+0x375/0x490
ret_from_fork+0x4dc/0x810
ret_from_fork_asm+0x11/0x20
</TASK>

Fix by querying the vport's own HCA caps to size the buffer correctly.
Refactor the function to allocate and return the MAC list internally,
removing the caller's dependency on knowing the correct max.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8726-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8727-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-8760-1 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-8726-2 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-8781-1 Linux kernel (NVIDIA Tegra) vulnerabilities
Ubuntu USN Ubuntu USN USN-8726-3 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8800-1 Linux kernel (NVIDIA BaseOS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8760-2 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-8726-4 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-3 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-8903-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8904-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8905-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-8906-1 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8903-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8905-2 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-9025-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-9066-1 Linux kernel (HWE) vulnerabilities
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 8.7, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:H'}

Type Values Removed Values Added
Weaknesses CWE-125
CWE-129
Type Values Removed Values Added
Weaknesses CWE-787
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate

Type Values Removed Values Added
Weaknesses CWE-125
CWE-129
Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list mlx5_query_nic_vport_mac_list() sizes its firmware command buffer using the PF's log_max_current_uc/mc_list capabilities. When querying a VF vport with a larger configured max (via devlink), the firmware response can overflow this buffer: BUG: KASAN: slab-out-of-bounds in mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] Read of size 4 at addr ff1100013ffc8a12 by task kworker/u96:2/385 CPU: 12 UID: 0 PID: 385 Comm: kworker/u96:2 Not tainted 7.0.0-rc6+ #1 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) Workqueue: mlx5_esw_wq esw_vport_change_handler [mlx5_core] Call Trace: <TASK> dump_stack_lvl+0x69/0xa0 print_report+0x176/0x4e4 kasan_report+0xc8/0x100 mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] esw_update_vport_addr_list+0x2e3/0xda0 [mlx5_core] esw_vport_change_handle_locked+0xa1f/0x1060 [mlx5_core] esw_vport_change_handler+0x6a/0x90 [mlx5_core] process_one_work+0x87f/0x15e0 worker_thread+0x62b/0x1020 kthread+0x375/0x490 ret_from_fork+0x4dc/0x810 ret_from_fork_asm+0x11/0x20 </TASK> Fix by querying the vport's own HCA caps to size the buffer correctly. Refactor the function to allocate and return the MAC list internally, removing the caller's dependency on knowing the correct max.
Title net/mlx5: Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Oct 30, 2026, 12:26 PM
Reserved
Jun 9, 2026, 7:44 AM
Status
Modified
Published
Jun 25, 2026, 9:16 AM
Modified
Oct 30, 2026, 1:19 PM
Severity
Moderate
Public date
Jun 25, 2026, 12:00 AM