Linux Kernel up to 6.12.62/6.17.12/6.18.1 block bio_alloc memory leak

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.12.62/6.17.12/6.18.1. This vulnerability affects the function bio_alloc of the component block. The manipulation results in memory leak. This vulnerability is identified as CVE-2025-68348. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.12.62/6.17.12/6.18.1. It has been classified as critical. Affected is the function bio_alloc of the component block. The manipulation with an unknown input leads to a memory leak vulnerability. CWE is classifying the issue as CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: block: fix memory leak in __blkdev_issue_zero_pages Move the fatal signal check before bio_alloc() to prevent a memory leak when BLKDEV_ZERO_KILLABLE is set and a fatal signal is pending. Previously, the bio was allocated before checking for a fatal signal. If a signal was pending, the code would break out of the loop without freeing or chaining the just-allocated bio, causing a memory leak. This matches the pattern already used in __blkdev_issue_write_zeroes() where the signal check precedes the allocation.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-68348 since 12/16/2025. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 279791 (Linux Distros Unpatched Vulnerability : CVE-2025-68348), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.63, 6.17.13, 6.18.2 or 6.19-rc1 eliminates this vulnerability. Applying the patch 453e4b0c84d0db1454ff0adf655d91179e6fca3a/7957635c679e8a01147163a3a4a1f16e1210fa03/7193407bc4457212fa38ec3aff9c640e63a8dbef/f7e3f852a42d7cd8f1af2c330d9d153e30c8adcf 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 databases at Tenable (279791) and CERT Bund (WID-SEC-2025-2920). Once again VulDB remains the best source for vulnerability data.

Affected

• Open Source Linux Kernel

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
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3
• 6.17.4
• 6.17.5
• 6.17.6
• 6.17.7
• 6.17.8
• 6.17.9
• 6.17.10
• 6.17.11
• 6.17.12
• 6.18.0
• 6.18.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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