CVE-2025-39963: io_uring: fix incorrect io_kiocb reference in io_link_skb

Published Oct 9, 2025
·
Updated

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

iouring: fix incorrect iokiocb reference in iolinkskb

In iolinkskb function, there is a bug where prevnotif is incorrectly assigned using 'nd' instead of 'prevnd'. This causes the context validation check to compare the current notification with itself instead of comparing it with the previous notification.

Fix by using the correct prevnd parameter when obtaining prevnotif.

Affected Software

9 affected components
Linux Kernel
Linux Linux kernel>=6.10<6.12.49
Linux Linux kernel>=6.13<6.16.9
Linux Linux kernel=6.17-rc1
Linux Linux kernel=6.17-rc2
Linux Linux kernel=6.17-rc3
Linux Linux kernel=6.17-rc4
Linux Linux kernel=6.17-rc5
Linux Linux kernel=6.17-rc6

Event History

Oct 9, 2025
CVE Published
via MITRE·12:13 PM
Data Sourced
via MITRE·12:13 PM
DescriptionSeverity
Data Sourced
via NVD·01:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-39963?

CVE-2025-39963 has been classified as a moderate severity vulnerability.

2

How do I fix CVE-2025-39963?

To fix CVE-2025-39963, you should upgrade to the latest version of the Linux Kernel that includes the patch for this vulnerability.

3

What systems are affected by CVE-2025-39963?

CVE-2025-39963 affects systems running vulnerable versions of the Linux Kernel.

4

What is the impact of CVE-2025-39963?

The impact of CVE-2025-39963 can lead to improper context validation, potentially allowing unauthorized access or manipulation.

5

Is there a workaround for CVE-2025-39963?

There is no known workaround for CVE-2025-39963; the best approach is to apply the patch by updating the kernel.

Contact

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