---
id: CVE-2026-23154
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: fix segmentation of forwarding fraglist GRO

  This patch enhances GSO segment handling by properly checking
  the SKB_GSO_DODGY flag for frag_list GSO packets, addres…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: fix segmentation of forwarding fraglist GRO

  This patch enhances GSO segment handling by properly checking
  the SKB_GSO_DODGY flag for frag_list GSO packets, addres…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 5.6, < 6.12.69'
  - 'linux_kernel >= 6.13, < 6.18.9'
  - linux_kernel = 6.19
patched:
  - linux_kernel 6.18.9
published: '2026-02-14'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:18:43.383'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-23154'
references:
  - url: 'https://git.kernel.org/stable/c/2cbef9ea5a0ac51863ede35c45f26931a85d3888'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3d48d59235c494d34e32052f768393111c0806ef'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3e62db1e3140449608975e29e0979cc5f3b1cc07'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/426ca15c7f6cb6562a081341ca88893a50c59fa2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9122d7280b2303e835cdfec156bd932ac1f586ed'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-082556.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-457936.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-784472.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00186
epssPercentile: 0.08115
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-06-10T20:41:02.301817Z'
ingestedAt: '2026-09-08T15:33:26.993Z'
---

## Overview

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

net: fix segmentation of forwarding fraglist GRO

This patch enhances GSO segment handling by properly checking
the SKB_GSO_DODGY flag for frag_list GSO packets, addressing
low throughput issues observed when a station accesses IPv4
servers via hotspots with an IPv6-only upstream interface.

Specifically, it fixes a bug in GSO segmentation when forwarding
GRO packets containing a frag_list. The function skb_segment_list
cannot correctly process GRO skbs that have been converted by XLAT,
since XLAT only translates the header of the head skb. Consequently,
skbs in the frag_list may remain untranslated, resulting in protocol
inconsistencies and reduced throughput.

To address this, the patch explicitly sets the SKB_GSO_DODGY flag
for GSO packets in XLAT's IPv4/IPv6 protocol translation helpers
(bpf_skb_proto_4_to_6 and bpf_skb_proto_6_to_4). This marks GSO
packets as potentially modified after protocol translation. As a
result, GSO segmentation will avoid using skb_segment_list and
instead falls back to skb_segment for packets with the SKB_GSO_DODGY
flag. This ensures that only safe and fully translated frag_list
packets are processed by skb_segment_list, resolving protocol
inconsistencies and improving throughput when forwarding GRO packets
converted by XLAT.

## Affected

- `linux_kernel >= 5.6, < 6.12.69`
- `linux_kernel >= 6.13, < 6.18.9`
- `linux_kernel = 6.19`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.18.9`