---
id: CVE-2026-86566
title: A flaw was found in DPDK lib/vhost
summary: >-
  A flaw was found in DPDK lib/vhost. A guest with runt RX descriptors can
  underflow the copy length in vhost enqueue, causing a denial of service in a
  shared vhost backend such as OVS-DPDK.
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H'
cwe:
  - CWE-191
published: '2026-10-14'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T20:17:59.953'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-86566'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-86566'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2529684'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-86566.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-86566'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-86566'
  - url: 'https://access.redhat.com/errata/RHSA-2026:94629'
    label: 'RHSA-2026:94629'
  - url: 'https://access.redhat.com/errata/RHSA-2026:94630'
    label: 'RHSA-2026:94630'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ingestedAt: '2026-10-14T18:47:39.317Z'
vendor: Red Hat
product: grout
affected:
  - grout (all versions)
  - openvswitch3.5 (all versions)
  - openvswitch3.6 (all versions)
  - openvswitch2.11 (all versions)
  - openvswitch2.12 (all versions)
  - openvswitch2.13 (all versions)
  - openvswitch2.15 (all versions)
  - openvswitch2.16 (all versions)
  - openvswitch2.17 (all versions)
  - openvswitch3.1 (all versions)
  - grout (all versions)
  - openvswitch2.17 (all versions)
  - openvswitch3.0 (all versions)
  - openvswitch3.1 (all versions)
  - openvswitch3.2 (all versions)
  - openvswitch3.3 (all versions)
  - openvswitch3.4 (all versions)
  - openvswitch3.5 (all versions)
  - openvswitch3.6 (all versions)
  - dpdk (all versions)
  - dpdk (all versions)
  - dpdk (all versions)
  - openvswitch2.17 (all versions)
  - openvswitch3.0 (all versions)
  - openvswitch3.1 (all versions)
  - openvswitch (all versions)
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-14T19:34:33.634479Z'
epss: 0.00177
epssPercentile: 0.07379
---

## Overview

A flaw was found in DPDK lib/vhost. A guest with runt RX descriptors can underflow the copy length in vhost enqueue, causing a denial of service in a shared vhost backend such as OVS-DPDK.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Fast Datapath for RHEL 10, Fast Datapath for RHEL 8, Fast Datapath for RHEL 9, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · no fix planned: Fast Datapath for RHEL 10, Fast Datapath for RHEL 8, Fast Datapath for RHEL 9, Red Hat OpenShift Container Platform 4, … · updated 2026-10-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-86566.json)