Microsoft Security Response Center guidance
Vendor revision: Nov 5, 2026Release Notes
Vulnerability intelligence
CVE-2026-43199 and is rated High severity with a CVSS score of 7.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix "scheduling while atomic" in IPsec MAC address query
Fix a "scheduling while atomic" bug in mlx5e_ipsec_init_macs() by replacing mlx5_query_mac_address() with ether_addr_copy() to get the local MAC address directly from netdev->dev_addr.
The issue occurs because mlx5_query_mac_address() queries the hardware which involves mlx5_cmd_exec() that can sleep, but it is called from the mlx5e_ipsec_handle_event workqueue which runs in atomic context.
The MAC address is already available in netdev->dev_addr, so no need to query hardware. This avoids the sleeping call and resolves the bug.
Call trace: BUG: scheduling while atomic: kworker/u112:2/69344/0x00000200 __schedule+0x7ab/0xa20 schedule+0x1c/0xb0 schedule_timeout+0x6e/0xf0 __wait_for_common+0x91/0x1b0 cmd_exec+0xa85/0xff0 [mlx5_core] mlx5_cmd_exec+0x1f/0x50 [mlx5_core] mlx5_query_nic_vport_mac_address+0x7b/0xd0 [mlx5_core] mlx5_query_mac_address+0x19/0x30 [mlx5_core] mlx5e_ipsec_init_macs+0xc1/0x720 [mlx5_core] mlx5e_ipsec_build_accel_xfrm_attrs+0x422/0x670 [mlx5_core] mlx5e_ipsec_handle_event+0x2b9/0x460 [mlx5_core] process_one_work+0x178/0x2e0 worker_thread+0x2ea/0x430
Source: NVD