cbcvebase.
CVE-2026-23440
published 2026-04-03

CVE-2026-23440: In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix race condition during IPSec ESN update In IPSec full offload mode, the…

PriorityP419medium4.7CVSS 3.1
AVLACHPRLUINSUCNINAH
EPSS
0.21%
10.8th percentile
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix race condition during IPSec ESN update In IPSec full offload mode, the device reports an ESN (Extended Sequence Number) wrap event to the driver. The driver validates this event by querying the IPSec ASO and checking that the esn_event_arm field is 0x0, which indicates an event has occurred. After handling the event, the driver must re-arm the context by setting esn_event_arm back to 0x1. A race condition exists in this handling path. After validating the event, the driver calls mlx5_accel_esp_modify_xfrm() to update the kernel's xfrm state. This function temporarily releases and re-acquires the xfrm state lock. So, need to acknowledge the event first by setting esn_event_arm to 0x1. This prevents the driver from reprocessing the same ESN update if the hardware sends events for other reason. Since the next ESN update only occurs after nearly 2^31 packets are received, there's no risk of missing an update, as it will happen long after this handling has finished. Processing the event twice causes the ESN high-order bits (esn_msb) to be incremented incorrectly. The driver then programs the hardware with this invalid ESN state, which leads to anti-replay failures and a complete halt of IPSec traffic. Fix this by re-arming the ESN event immediately after it is validated, before calling mlx5_accel_esp_modify_xfrm(). This ensures that any spurious, duplicate events are correctly ignored, closing the race window.

Affected

43 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.19.10-1 (forky)linux 6.19.10-1 (forky)
linuxlinux
linuxlinux>= fef06678931ff67b158d337b581e5cf5ca40a3a3 < 3dffc083292e6872787bd7e34b957627622f9af43dffc083292e6872787bd7e34b957627622f9af4
linuxlinux>= fef06678931ff67b158d337b581e5cf5ca40a3a3 < 2051c709dce92da3550040aa7949cd5a9c89b14e2051c709dce92da3550040aa7949cd5a9c89b14e
linuxlinux>= fef06678931ff67b158d337b581e5cf5ca40a3a3 < 96c9c25b74686ac2de15921c9ad30c5ef13af8cd96c9c25b74686ac2de15921c9ad30c5ef13af8cd
linuxlinux>= fef06678931ff67b158d337b581e5cf5ca40a3a3 < 8d625c15471fb8780125eaef682983a96af77bdc8d625c15471fb8780125eaef682983a96af77bdc
linuxlinux>= fef06678931ff67b158d337b581e5cf5ca40a3a3 < beb6e2e5976a128b0cccf10d158124422210c5efbeb6e2e5976a128b0cccf10d158124422210c5ef
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.19.10-16.19.10-1
linuxlinux_kernel>= 6.13 < 6.18.206.18.20
linuxlinux_kernel>= 6.19 < 6.19.106.19.10
linuxlinux_kernel>= 6.4.1 < 6.6.1306.6.130
linuxlinux_kernel>= 6.7 < 6.12.786.12.78
ubuntulinux
ubuntulinux-aws
ubuntulinux-azure
ubuntulinux-azure-6.8
ubuntulinux-azure-fde

CVSS provenance

nvdv3.14.7MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
vendor_redhat4.7MEDIUM
vendor_ubuntu2.0LOW
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