Linux Kernel up to 6.1.128/6.6.77/6.12.13/6.13.2 blkdev_read_iter data authenticity

Summaryinfo

A vulnerability labeled as problematic has been found in Linux Kernel up to 6.1.128/6.6.77/6.12.13/6.13.2. This impacts the function blkdev_read_iter. Such manipulation leads to data authenticity. This vulnerability is listed as CVE-2025-21832. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.128/6.6.77/6.12.13/6.13.2 and classified as problematic. Affected by this issue is the function blkdev_read_iter. The manipulation with an unknown input leads to a data authenticity vulnerability. Using CWE to declare the problem leads to CWE-345. The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: block: don't revert iter for -EIOCBQUEUED blkdev_read_iter() has a few odd checks, like gating the position and count adjustment on whether or not the result is bigger-than-or-equal to zero (where bigger than makes more sense), and not checking the return value of blkdev_direct_IO() before doing an iov_iter_revert(). The latter can lead to attempting to revert with a negative value, which when passed to iov_iter_revert() as an unsigned value will lead to throwing a WARN_ON() because unroll is bigger than MAX_RW_COUNT. Be sane and don't revert for -EIOCBQUEUED, like what is done in other spots.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2025-21832 since 12/29/2024. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 232265 (Linux Distros Unpatched Vulnerability : CVE-2025-21832), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.129, 6.6.78, 6.12.14, 6.13.3 or 6.14-rc1 eliminates this vulnerability. Applying the patch 6c26619effb1b4cb7d20b4e666ab8f71f6a53ccb/84671b0630ccb46ae9f1f99a45c7d63ffcd6a474/68f16d3034a06661245ecd22f0d586a8b4e7c473/a58f136bad29f9ae721a29d98c042fddbee22f77/b13ee668e8280ca5b07f8ce2846b9957a8a10853 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 (232265) and CERT Bund (WID-SEC-2025-0499). Once again VulDB remains the best source for vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• SolarWinds Security Event Manager
• Open Source Linux Kernel
• Dell Secure Connect Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.128
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.6.55
• 6.6.56
• 6.6.57
• 6.6.58
• 6.6.59
• 6.6.60
• 6.6.61
• 6.6.62
• 6.6.63
• 6.6.64
• 6.6.65
• 6.6.66
• 6.6.67
• 6.6.68
• 6.6.69
• 6.6.70
• 6.6.71
• 6.6.72
• 6.6.73
• 6.6.74
• 6.6.75
• 6.6.76
• 6.6.77
• 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
• 6.13.0
• 6.13.1
• 6.13.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

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CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

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