High 8.7Published Jun 25, 2026

CVE-2026-53230net/mlx5: Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list

Updated under an hour ago (Oct 27, 2026, 9:23 PM ET)

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Exploited in the last 30 days

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.

CVSS: 8.7 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:H
Weakness (CWE): CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from e16aea2744abea612c27ee0eef606c6a6a8204de before 41781f2789309462520a93822e946521ed78f97f; from e16aea2744abea612c27ee0eef606c6a6a8204de before 537d87784e81c3d7037525b99416455cee088cdc; from e16aea2744abea612c27ee0eef606c6a6a8204de before 0f807764bb122fd63aa45f4229cb1ef2679fbd40; from e16aea2744abea612c27ee0eef606c6a6a8204de before 2398e497389ed4be43f7cfbab499b49cec7dae1a; from e16aea2744abea612c27ee0eef606c6a6a8204de before 894e036a24a26a6dd7b17d8d3fb5c53ab48a6074	CNA record
linux linux_kernel linux:linux_kernel	from 4.5 before 6.6.143; from 6.7 before 6.12.94; from 6.13 before 6.18.36; from 6.19 before 7.0.13; 7.1; 7.1; 7.1; 7.1; and 3 more ranges	NVD

References

References

https://git.kernel.org/stable/c/41781f2789309462520a93822e946521ed78f97f	patch
https://git.kernel.org/stable/c/537d87784e81c3d7037525b99416455cee088cdc	patch
https://git.kernel.org/stable/c/0f807764bb122fd63aa45f4229cb1ef2679fbd40	patch
https://git.kernel.org/stable/c/2398e497389ed4be43f7cfbab499b49cec7dae1a	patch
https://git.kernel.org/stable/c/894e036a24a26a6dd7b17d8d3fb5c53ab48a6074	patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.