---
id: CVE-2026-46321
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  tun: free page on short-frame rejection in tun_xdp_one()

  tun_xdp_one() returns -EINVAL on a frame shorter than ETH_HLEN without
  freeing the page that vhost_net_build_x…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  tun: free page on short-frame rejection in tun_xdp_one()

  tun_xdp_one() returns -EINVAL on a frame shorter than ETH_HLEN without
  freeing the page that vhost_net_build_x…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 5.4.281, < 5.5'
  - 'linux_kernel >= 5.10.223, < 5.10.259'
  - 'linux_kernel >= 5.15.164, < 5.15.210'
  - 'linux_kernel >= 6.1.102, < 6.1.176'
  - 'linux_kernel >= 6.6.43, < 6.6.143'
  - 'linux_kernel >= 6.9.12, < 6.10'
  - 'linux_kernel >= 6.10.2, < 6.12.93'
  - 'linux_kernel >= 6.13, < 6.18.35'
  - 'linux_kernel >= 6.19, < 7.0.12'
  - linux_kernel = 7.1
patched:
  - linux_kernel 7.0.12
published: '2026-06-09'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:19:53.553'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-46321'
references:
  - url: 'https://git.kernel.org/stable/c/0a6f46a9332ad6958992d64d3b3a81a80b2ca940'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/0e8211fcf9426f5adddf32516ba0f400ceb9544d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/37a1c268c2c8090bf4dc552d732bd23ba36f8eb0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5b34f9e4fe2f203724a6e893d6df0316b9670057'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/69863ff2720a0e9871f1a5710f2a33a94217fee0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/98c67be9eb9de72465a071949e84a3cdb8fab5a3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e915445942af6dcea628bf66d6241641201a0c41'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f4feb1e20058e407cb00f45aff47f5b7e19a6bbf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-784472.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00129
epssPercentile: 0.02232
ingestedAt: '2026-10-15T03:30:12.899Z'
---

## Overview

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

tun: free page on short-frame rejection in tun_xdp_one()

tun_xdp_one() returns -EINVAL on a frame shorter than ETH_HLEN without
freeing the page that vhost_net_build_xdp() allocated for it.
tun_sendmsg() discards that -EINVAL and still returns total_len, so
vhost_tx_batch() takes the success path and never frees the page; each
short frame in a batch leaks one page-frag chunk.

A local process that can open /dev/net/tun and /dev/vhost-net can hit
this path: it attaches a tun/tap device as the vhost-net backend and
feeds TX descriptors whose length minus the virtio-net header is below
ETH_HLEN. Each kick leaks the page-frag chunks for that batch, and a
tight submission loop exhausts host memory and triggers an OOM panic.
Free the page before returning -EINVAL, matching the XDP-program error
path in the same function.

## Affected

- `linux_kernel >= 5.4.281, < 5.5`
- `linux_kernel >= 5.10.223, < 5.10.259`
- `linux_kernel >= 5.15.164, < 5.15.210`
- `linux_kernel >= 6.1.102, < 6.1.176`
- `linux_kernel >= 6.6.43, < 6.6.143`
- `linux_kernel >= 6.9.12, < 6.10`
- `linux_kernel >= 6.10.2, < 6.12.93`
- `linux_kernel >= 6.13, < 6.18.35`
- `linux_kernel >= 6.19, < 7.0.12`
- `linux_kernel = 7.1`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.12`