CVE-2026-43393: btrfs: fix chunk map leak in btrfs_map_block() after btrfs_chunk_map_num_copies()

Q: Who is exposed to this issue?

Systems running the Linux kernel with Btrfs in use are the relevant population. The flaw is in the Btrfs block-mapping path and can leak a chunk map when that path returns -EINVAL.

Q: What level of access does an attacker need?

The CVSS vector indicates local access and low privileges are required. No user interaction is required.

Q: What is the likely impact?

The reported impact is availability only: CVSS assigns no confidentiality or integrity impact and a high availability impact. The issue is a resource leak that can result from the affected error path.

Q: Is a fix available?

Yes. A patch is available, with stable kernel references provided for the fix.

Published May 8, 2026

Updated

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

btrfs: fix chunk map leak in btrfsmapblock() after btrfschunkmapnumcopies()

Fix a chunk map leak in btrfsmapblock(): if we return early with -EINVAL, we're not freeing the chunk map that we've just looked up.

Affected Software

6 affected components

Linux Linux kernel

Linux Linux kernel>=6.12<6.12.78

Linux Linux kernel>=6.13<6.18.19

Linux Linux kernel>=6.19<6.19.9

Linux Linux kernel=7.0-rc1

Linux Linux kernel=7.0-rc2

Remediation

Event History

May 8, 2026

CVE Published

via MITRE·02:21 PM

Data Sourced

via MITRE·02:21 PM

Description

Data Sourced

via NVD·03:16 PM

RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

Who is exposed to this issue?

Systems running the Linux kernel with Btrfs in use are the relevant population. The flaw is in the Btrfs block-mapping path and can leak a chunk map when that path returns -EINVAL.

What level of access does an attacker need?

The CVSS vector indicates local access and low privileges are required. No user interaction is required.

What is the likely impact?

The reported impact is availability only: CVSS assigns no confidentiality or integrity impact and a high availability impact. The issue is a resource leak that can result from the affected error path.

Is a fix available?

Yes. A patch is available, with stable kernel references provided for the fix.

CVE-2026-43393: btrfs: fix chunk map leak in btrfs_map_block() after btrfs_chunk_map_num_copies()

Affected Software

Remediation

Patch Available

Patch Available

Patch Available

Patch Available

Event History

Frequently Asked Questions

Who is exposed to this issue?

What level of access does an attacker need?

What is the likely impact?

Is a fix available?

Company

Resources

Contact

Frequently Asked Questions

Who is exposed to this issue?

What level of access does an attacker need?

What is the likely impact?

Is a fix available?