---
id: "CVE-2026-98561"
kind: "vulnerability"
aliases: ["CVE-2026-98561"]
title: "Linux kernel nfp driver: IPsec RX use-after-free race on state refcount"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "ipsec", "linux-kernel", "nfp-driver", "smartnic"]
not_affected_if: ["no-ipsec-offload", "no-nfp-hardware"]
published_at: "2026-10-18T16:17:08+00:00"
first_seen_at: "2026-10-23T21:57:15+00:00"
updated_at: "2026-10-25T05:23:23+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98561", "first_seen_at": "2026-10-23T21:57:15+00:00"}]
---

# Linux kernel nfp driver: IPsec RX use-after-free race on state refcount

In the Linux kernel's nfp Netronome network driver, the IPsec receive path could take a reference to an xfrm_state after it had been queued for destruction, a refcount race. The sources do not state what an attacker gets at worst.

_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 commit resolving the nfp IPsec RX state locking; the sources do not name a fixed version.

## Timeline

- 2026-10-23T21:57:15+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98561

## From the sources

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

nfp: hold IPsec RX state under the XArray lock

nfp_net_ipsec_rx() drops the XArray lock before taking a reference to the
xfrm_state it found. The delete path can erase the entry and drop the last
state reference in that interval. RX can then try to increment a zero
refcount after the state has been queued for destruction.

The driver queues firmware invalidation asynchronously; the delete path
does not wait for the command to complete or drain pending RX processing.

The XFRM garbage collector waits for an RCU grace period before freeing
the state. That delays reclamation but does not make acquiring a reference
from zero valid.

Take the xfrm_state reference before releasing the XArray lock so
xa_erase() cannot run between lookup and reference acquisition.

---

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