CVE-2025-40080: nbd: restrict sockets to TCP and UDP

Published Oct 28, 2025
·
Updated

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

nbd: restrict sockets to TCP and UDP

Recently, syzbot started to abuse NBD with all kinds of sockets.

Commit cf1b2326b734 ("nbd: verify socket is supported during setup") made sure the socket supported a shutdown() method.

Explicitely accept TCP and UNIX stream sockets.

Affected Software

3 affected componentsFixes available
Linux Kernel
Microsoft azl3 kernel 6.6.104.2-4
Microsoft azl3 kernel 6.6.104.2-4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Compensating control

    Restrict NBD sockets to TCP and UDP during setup so that only supported socket types are accepted (per: "nbd: restrict sockets to TCP and UDP" / verify supported sockets including shutdown() support).

Event History

Oct 28, 2025
CVE Published
via MITRE·11:48 AM
Data Sourced
via MITRE·11:48 AM
Description
Data Sourced
via NVD·12:15 PM
Description
Oct 29, 2025
Data Sourced
via Microsoft·01:03 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·01:03 AM
Affected Software
Updated
via Microsoft·01:03 AM
DescriptionSeverity

Frequently Asked Questions

1

What is the severity of CVE-2025-40080?

The severity of CVE-2025-40080 has not been explicitly rated, but it involves a vulnerability in the Linux kernel regarding unsupported socket types.

2

How do I fix CVE-2025-40080?

To fix CVE-2025-40080, update to the latest version of the Linux kernel where this vulnerability has been addressed.

3

What versions of Linux Kernel are affected by CVE-2025-40080?

All versions of the Linux kernel prior to the application of the patch related to CVE-2025-40080 are affected.

4

What is the impact of CVE-2025-40080 on system security?

CVE-2025-40080 could potentially allow unauthorized access to kernel-level resources, impacting system security.

5

Has CVE-2025-40080 been exploited in the wild?

As of now, there is no public information indicating that CVE-2025-40080 has been actively exploited in the wild.

Contact

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