---
id: "CVE-2026-98497"
kind: "vulnerability"
aliases: ["CVE-2026-98497"]
title: "Linux kernel: swapped IPv6 IPsec masks on Mellanox NICs misroute traffic"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "ipsec", "ipv6", "linux-kernel", "mlx5", "self-hosted"]
not_affected_if: ["no-ipv6-ipsec-policy", "no-mlx5-ipsec-offload"]
published_at: "2026-10-18T16:17:00+00:00"
first_seen_at: "2026-10-23T21:57:15+00:00"
updated_at: "2026-10-25T05:25:37+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98497", "first_seen_at": "2026-10-23T21:57:15+00:00"}]
---

# Linux kernel: swapped IPv6 IPsec masks on Mellanox NICs misroute traffic

In the Linux kernel's mlx5e driver for Mellanox ConnectX NICs, IPv6 IPsec policy masks were installed in the wrong address fields when source and destination prefix lengths differ. The resulting hardware rule can miss traffic the policy should cover and match traffic outside it.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- unknown

## Fix

- Update to a Linux kernel release that includes the upstream fix 'net/mlx5e: fix swapped IPv6 IPsec policy masks' (exact version unknown from sources)

## Timeline

- 2026-10-23T21:57:15+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98497

## From the sources

In the Linux kernel, the following vulnerability has been resolved:

net/mlx5e: fix swapped IPv6 IPsec policy masks

IPv6 XFRM policies may use different source and destination prefix
lengths. mlx5e_ipsec_policy_mask() builds the corresponding masks
independently, but setup_fte_addr6() installs each mask in the opposite
address field.

When the prefix lengths differ, this makes the source match use the
destination prefix and the destination match use the source prefix. The
resulting hardware rule can both miss traffic covered by the policy and
match traffic outside it.

Install each mask in its corresponding match field.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_