---
id: CVE-2025-38574
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  pptp: ensure minimal skb length in pptp_xmit()

  Commit aabc6596ffb3 ("net: ppp: Add bound checking for skb data
  on ppp_sync_txmung") fixed ppp_sync_txmunge()

  We need a…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  pptp: ensure minimal skb length in pptp_xmit()

  Commit aabc6596ffb3 ("net: ppp: Add bound checking for skb data
  on ppp_sync_txmung") fixed ppp_sync_txmunge()

  We need a…
severity: high
cvss: 8.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H'
cwe:
  - CWE-908
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.13, < 5.4.297'
  - 'linux_kernel >= 5.5, < 5.10.241'
  - 'linux_kernel >= 5.11, < 5.15.190'
  - 'linux_kernel >= 5.16, < 6.1.148'
  - 'linux_kernel >= 6.2, < 6.6.102'
  - 'linux_kernel >= 6.7, < 6.12.42'
  - 'linux_kernel >= 6.13, < 6.15.10'
  - 'linux_kernel >= 6.16, < 6.16.1'
  - linux_kernel = 2.6.12
  - debian_linux = 11.0
patched:
  - linux_kernel 6.16.1
published: '2025-08-19'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T22:18:45.977'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-38574'
references:
  - url: 'https://git.kernel.org/stable/c/1a04db0fd75cb6034fc27a56b67b3b8b9022a98c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/26672f1679b143aa34fca0b6046b7fd0c184770d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5005d24377378a20e5c0e53052fc4ebdcdcbc611'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/504cc4ab91073d2ac7404ad146139f86ecee7193'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5de7513f38f3c19c0610294ee478242bea356f8c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/97b8c5d322c5c0038cac4bc56fdbe237d0be426f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b7dcda76fd0615c0599c89f36873a6cd48e02dbb'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/de9c4861fb42f0cd72da844c3c34f692d5895b7b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ea99b88b1999ebcb24d5d3a6b7910030f40d3bba'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
  - cve.org
epss: 0.00385
epssPercentile: 0.32355
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-15T21:51:52.634407Z'
ingestedAt: '2026-10-15T22:48:25.514Z'
---

## Overview

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

pptp: ensure minimal skb length in pptp_xmit()

Commit aabc6596ffb3 ("net: ppp: Add bound checking for skb data
on ppp_sync_txmung") fixed ppp_sync_txmunge()

We need a similar fix in pptp_xmit(), otherwise we might
read uninit data as reported by syzbot.

BUG: KMSAN: uninit-value in pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193
  pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193
  ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2290 [inline]
  ppp_input+0x1d6/0xe60 drivers/net/ppp/ppp_generic.c:2314
  pppoe_rcv_core+0x1e8/0x760 drivers/net/ppp/pppoe.c:379
  sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148
  __release_sock+0x1d3/0x330 net/core/sock.c:3213
  release_sock+0x6b/0x270 net/core/sock.c:3767
  pppoe_sendmsg+0x15d/0xcb0 drivers/net/ppp/pppoe.c:904
  sock_sendmsg_nosec net/socket.c:712 [inline]
  __sock_sendmsg+0x330/0x3d0 net/socket.c:727
  ____sys_sendmsg+0x893/0xd80 net/socket.c:2566
  ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620
  __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2709

## Affected

- `linux_kernel >= 2.6.13, < 5.4.297`
- `linux_kernel >= 5.5, < 5.10.241`
- `linux_kernel >= 5.11, < 5.15.190`
- `linux_kernel >= 5.16, < 6.1.148`
- `linux_kernel >= 6.2, < 6.6.102`
- `linux_kernel >= 6.7, < 6.12.42`
- `linux_kernel >= 6.13, < 6.15.10`
- `linux_kernel >= 6.16, < 6.16.1`
- `linux_kernel = 2.6.12`
- `debian_linux = 11.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.16.1`