CVE-2021-3739: Null Pointer Dereference

Published Aug 26, 2021
·
Updated

A NULL pointer dereference flaw was found in btrfsrmdevice function in fs/btrfs/volumes.c in Linux Kernel, where triggering the bug requires ‘CAPSYSADMIN’. This could allow a local attacker to crash the system or leak kernel internal information.

References: https://lore.kernel.org/linux-btrfs/CAFcO6XO5TC5sEo-C9JGC75JkNAzkOSSLA3a=bwQqXFFbRTZ7Gw@mail.gmail.com/T/#md4b850f33616b7364f86e6fed144abc925f3669c https://lore.kernel.org/linux-btrfs/20210806102415.304717-1-wqu@suse.com/T/#u

Other sources

A NULL pointer dereference flaw was found in the btrfsrmdevice function in fs/btrfs/volumes.c in the Linux Kernel, where triggering the bug requires ‘CAPSYSADMIN’. This flaw allows a local attacker to crash the system or leak kernel internal information. The highest threat from this vulnerability is to system availability.

Launchpad

Affected Software

51 affected componentsFixes available
Linux Linux kernel<=5.14.20
Fedoraproject Fedora=34
NetApp Baseboard Management Controller H300s Firmware
NetApp Baseboard Management Controller H300s
NetApp Baseboard Management Controller H500s Firmware
NetApp Baseboard Management Controller H500s
NetApp Baseboard Management Controller H700s Firmware
NetApp Baseboard Management Controller H700s
NetApp Baseboard Management Controller H300e Firmware
NetApp Baseboard Management Controller H300e
NetApp Baseboard Management Controller H500e Firmware
NetApp Baseboard Management Controller H500e
NetApp Baseboard Management Controller H700e Firmware
NetApp Baseboard Management Controller H700e
NetApp Baseboard Management Controller H410s Firmware
NetApp Baseboard Management Controller H410s
NetApp Baseboard Management Controller H410c Firmware
NetApp Baseboard Management Controller H410c
All of the following
NetApp H300s Firmware
NetApp H300s
All of the following
NetApp H500s Firmware
NetApp H500s
All of the following
NetApp H700s Firmware
NetApp H700s
All of the following
NetApp H300e Firmware
NetApp H300e
All of the following
NetApp H500e Firmware
NetApp H500e
All of the following
NetApp H700e Firmware
NetApp H700e
All of the following
NetApp H410s Firmware
NetApp H410s
All of the following
NetApp H410c Firmware
NetApp H410c
NetApp H300s Firmware
NetApp H300s
NetApp H500s Firmware
NetApp H500s
NetApp H700s Firmware
NetApp H700s
NetApp H300e Firmware
NetApp H300e
NetApp H500e Firmware
NetApp H500e
NetApp H700e Firmware
NetApp H700e
NetApp H410s Firmware
NetApp H410s
NetApp H410c Firmware
NetApp H410c
debian/linux
5.10.223-15.10.249-16.1.159-16.1.162-16.12.63-16.12.73-16.18.12-1

Event History

Aug 26, 2021
Data Sourced
via Red Hat·07:26 AM
DescriptionSeverityAffected Software
Mar 7, 2022
CVE Published
via MITRE·03:19 PM
Data Sourced
via MITRE·03:19 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:58 PM
Description
Feb 24, 2026
Data Sourced
via Ubuntu·09:17 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·09:18 PM
DescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2021-3739?

CVE-2021-3739 has a severity level that allows local attackers to crash the system or potentially leak sensitive kernel information.

2

How do I fix CVE-2021-3739?

To fix CVE-2021-3739, it is recommended to upgrade to a patched version of the Linux kernel, specifically 5.10.223-1, 5.10.226-1, or later.

3

Who is affected by CVE-2021-3739?

CVE-2021-3739 affects users running vulnerable Linux kernel versions up to 5.14.20 and certain NetApp firmware versions.

4

What causes CVE-2021-3739?

CVE-2021-3739 is caused by a NULL pointer dereference flaw in the btrfs_rm_device function within the Linux kernel.

5

Can CVE-2021-3739 be exploited remotely?

CVE-2021-3739 cannot be exploited remotely as it requires local access with CAP_SYS_ADMIN capabilities.

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