---
id: "CVE-2026-99286"
page: "https://infrastack.ai/live/CVE-2026-99286"
kind: "vulnerability"
aliases: ["CVE-2026-99286"]
title: "Linux kernel: xen-netback connection failure cleanup race can read invalid queues"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "linux-kernel", "xen", "xen-netback"]
not_affected_if: ["no-xen-backend"]
published_at: "2026-11-10T19:22:31+00:00"
first_seen_at: "2026-11-10T19:25:35+00:00"
updated_at: "2026-11-10T20:04:41+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99286", "first_seen_at": "2026-11-10T19:25:35+00:00"}]
exploit_sources: []
---

# Linux kernel: xen-netback connection failure cleanup race can read invalid queues

Link for people: https://infrastack.ai/live/CVE-2026-99286 (this .md is for agents)

In the Linux kernel's Xen network backend (xen-netback), a failed XenBus connection cleanup can leave the queue count visible to statistics readers while the queues are being torn down. The sources do not state what an attacker gains beyond a possible invalid memory access.

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

## Timeline

- 2026-11-10T19:25:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-99286

## From the sources

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

xen-netback: Fix XenBus connection failure cleanup

xenvif_get_stats and xenvif_get_ethtool_stats capture vif->num_queues
under rcu_read_lock. We need to unpublish vif->num_queues before
synchronize_net to ensure that readers that come afterwards will not
read a non-zero vif->num_queues and attempt to access invalid queues.

This is the same cleanup algorithm as used in backend_disconnect and
added in commit b17075d5c198 ("xen-netback: fix race condition on XenBus
disconnect").

This is XSA-531

---

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