CVE-2026-23440net/mlx5e: Fix race condition during IPSec ESN update
Updated under an hour ago ()
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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.
- CVSS
- 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- Not given
- 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 16, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from fef06678931ff67b158d337b581e5cf5ca40a3a3 before 3dffc083292e6872787bd7e34b957627622f9af4; from fef06678931ff67b158d337b581e5cf5ca40a3a3 before 2051c709dce92da3550040aa7949cd5a9c89b14e; from fef06678931ff67b158d337b581e5cf5ca40a3a3 before 96c9c25b74686ac2de15921c9ad30c5ef13af8cd; from fef06678931ff67b158d337b581e5cf5ca40a3a3 before 8d625c15471fb8780125eaef682983a96af77bdc; from fef06678931ff67b158d337b581e5cf5ca40a3a3 before beb6e2e5976a128b0cccf10d158124422210c5ef | CNA record |
linux linux_kernel linux:linux_kernel | from 6.4.1 before 6.6.130; from 6.7 before 6.12.78; from 6.13 before 6.18.20; from 6.19 before 6.19.10; 6.4; 7.0; 7.0; 7.0; and 4 more ranges | NVD |
References
- https://git.kernel.org/stable/c/3dffc083292e6872787bd7e34b957627622f9af4patch
- https://git.kernel.org/stable/c/2051c709dce92da3550040aa7949cd5a9c89b14epatch
- https://git.kernel.org/stable/c/96c9c25b74686ac2de15921c9ad30c5ef13af8cdpatch
- https://git.kernel.org/stable/c/8d625c15471fb8780125eaef682983a96af77bdcpatch
- https://git.kernel.org/stable/c/beb6e2e5976a128b0cccf10d158124422210c5efpatch
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.