Linux Kernel up to 6.12.77/6.18.18/6.19.8 btrfs btrfs_map_block memory leak

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.12.77/6.18.18/6.19.8. It has been declared as critical. Affected by this issue is the function btrfs_map_block of the component btrfs. Executing a manipulation can lead to an unknown weakness. This vulnerability is tracked as CVE-2026-43393. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.77/6.18.18/6.19.8. This vulnerability affects the function btrfs_map_block of the component btrfs. The CWE definition for the vulnerability is CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix chunk map leak in btrfs_map_block() after btrfs_chunk_map_num_copies() Fix a chunk map leak in btrfs_map_block(): if we return early with -EINVAL, we're not freeing the chunk map that we've just looked up.

The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-43393 since 05/01/2026. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 313457 (Linux Distros Unpatched Vulnerability : CVE-2026-43393), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.78, 6.18.19 or 6.19.9 eliminates this vulnerability. Applying the patch 0e4aaf5a3212b6a469c2489637c29a8e2a5062a5/7bdf00ed75c477252578068dba19934cd825f20a/4f90c5c2698383984102401b1724b0b67da832ab/f15fb3d41543244d1179f423da4a4832a55bc050 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (313457). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.12.59
• 6.12.60
• 6.12.61
• 6.12.62
• 6.12.63
• 6.12.64
• 6.12.65
• 6.12.66
• 6.12.67
• 6.12.68
• 6.12.69
• 6.12.70
• 6.12.71
• 6.12.72
• 6.12.73
• 6.12.74
• 6.12.75
• 6.12.76
• 6.12.77
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5
• 6.19.6
• 6.19.7
• 6.19.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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