CVE-2025-39825: smb: client: fix race with concurrent opens in rename(2)

Published Sep 16, 2025
·
Updated

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

smb: client: fix race with concurrent opens in rename(2)

Besides sending the rename request to the server, the rename process also involves closing any deferred close, waiting for outstanding I/O to complete as well as marking all existing open handles as deleted to prevent them from deferring closes, which increases the race window for potential concurrent opens on the target file.

Fix this by unhashing the dentry in advance to prevent any concurrent opens on the target.

Affected Software

9 affected componentsFixes available
Microsoft azl3 kernel 6.6.96.2-2
Linux Linux kernel>=5.13<6.1.150
Linux Linux kernel>=6.2<6.6.104
Linux Linux kernel>=6.7<6.12.45
Linux Linux kernel>=6.13<6.16.5
Linux Linux kernel=6.17-rc1
Debian Debian Linux=11.0
IBM DS8A00( R10.0 - R10.1 )<=10.1.3.0 - 10.11.35.0
IBM DS8900F ( R9.4)<=89.40.83.0-89.44.25.0

Event History

Sep 16, 2025
CVE Published
via MITRE·01:00 PM
Data Sourced
via MITRE·01:00 PM
DescriptionSeverity
Data Sourced
via NVD·01:16 PM
RemedyDescriptionSeverityWeaknessAffected Software
Data Sourced
via Red Hat·02:02 PM
DescriptionSeverityAffected Software
Sep 20, 2025
Data Sourced
via Microsoft·01:08 AM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·08:08 AM
DescriptionSeverity
Aug 19, 2026
Data Sourced
via IBM·12:00 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2025-39825?

The severity of CVE-2025-39825 is currently assessed as high due to the potential impact on file operations.

2

How do I fix CVE-2025-39825?

To fix CVE-2025-39825, ensure that your system is updated with the latest version of the affected Linux kernel.

3

Which software is affected by CVE-2025-39825?

CVE-2025-39825 affects the Microsoft azl3 kernel version 6.6.96.2-2.

4

What type of vulnerability is CVE-2025-39825?

CVE-2025-39825 is a race condition vulnerability that occurs during concurrent file renaming operations in the Linux kernel.

5

When was CVE-2025-39825 resolved?

CVE-2025-39825 was resolved in a recent patch release addressing the concurrent opening issues.

Contact

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