Skip to main content
VulnerabilityPublished Updated

CVE-2025-38432: Linux kernel · net: netpoll: Initialize UDP checksum field before checksumming

Affects Linux kernelSource GCVE Database

0
Compare

Not known to be exploited · CVSS 5.5 Medium.

Data as of 15 Nov 2026, 02:00 UTC

CVSS 3.1 base score
5.5Medium
How severe the flaw is on the 0–10 CVSS scale.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 25 Jul 2025

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 14 Nov 2026.

What to do

Affected software

ProductAffectedFixed in
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threatsAffected
  • 6.11.0-1008.8~24.04.1 – 6.11.0-1018.18~24.04.1
7 affected builds
Fixed in–
Ubuntu 24.04 LTSlinux-gcp-6.11pkg:deb/ubuntu/linux-gcp-6.11?arch=source&distro=nobleOther threatsAffected
  • 6.11.0-1006.6~24.04.2 – 6.11.0-1017.17~24.04.1
7 affected builds
Fixed in–
Ubuntu 24.04 LTSlinux-hwe-6.11pkg:deb/ubuntu/linux-hwe-6.11?arch=source&distro=nobleOther threatsAffected
  • 6.11.0-17.17~24.04.2 – 6.11.0-29.29~24.04.1
8 affected builds
Fixed in–
Ubuntu 24.04 LTSlinux-lowlatency-hwe-6.11pkg:deb/ubuntu/linux-lowlatency-hwe-6.11?arch=source&distro=nobleOther threatsAffected
  • 6.11.0-1009.10~24.04.1 – 6.11.0-1016.17~24.04.1
7 affected builds
Fixed in–
Ubuntu 24.04 LTSlinux-raspi-realtimepkg:deb/ubuntu/linux-raspi-realtime?arch=source&distro=nobleOther threatsAffected
  • =6.8.0-2019.20
Fixed in–
Ubuntu 24.04 LTSlinux-realtimepkg:deb/ubuntu/linux-realtime?arch=source&distro=nobleOther threatsAffected
  • =6.8.1-1015.16
Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix is available that restores the initialization of the UDP checksum field before checksum calculation. Users should apply the updated Linux kernel versions that address this issue. Since this is a kernel-level vulnerability, upgrading to patched kernel releases is the recommended remediation.

Description

CVE-2025-38432 is a medium severity vulnerability in the Linux kernel's netpoll component affecting UDP checksum initialization. A recent code change removed the initialization of the UDP checksum field, causing incorrect checksum calculation and breaking netpoll IPv6 transmission. The issue arises because the UDP checksum field (udph->check) must be set before invoking the checksum calculation function csum_ipv6_magic(). This flaw impacts specific Linux kernel versions used in various Ubuntu LTS releases.

References

Community reviews

Loading reviews…