Linux Kernel up to 5.12.8 NFS nfs_do_recoalesce pg_bytes_written out-of-bounds write

Summaryinfo

A vulnerability marked as problematic has been reported in Linux Kernel up to 5.12.8. The affected element is the function nfs_do_recoalesce of the component NFS. Performing a manipulation of the argument pg_bytes_written results in an unknown weakness. This vulnerability is known as CVE-2021-47166. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 5.12.8. This affects the function nfs_do_recoalesce of the component NFS. The manipulation of the argument pg_bytes_written with an unknown input leads to a unknown weakness. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: NFS: Don't corrupt the value of pg_bytes_written in nfs_do_recoalesce() The value of mirror->pg_bytes_written should only be updated after a successful attempt to flush out the requests on the list.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-47166. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 239742 (TencentOS Server 2: kernel (TSSA-2024:1030)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.4.271, 4.9.271, 4.14.235, 4.19.193, 5.4.124, 5.10.42, 5.12.9 or 5.13 eliminates this vulnerability. Applying the patch e8b8418ce14a/b291baae24f8/c757c1f1e65d/40f139a6d50c/785917316b25/7087db95c0a0/2fe1cac336b5/0d0ea309357d 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 (239742) and CERT Bund (WID-SEC-2024-0699). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• EMC Avamar
• Dell NetWorker
• Open Source Linux Kernel
• IBM Spectrum Protect Plus

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.4.270
• 4.9.270
• 4.14.234
• 4.19.192
• 5.4.123
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.10.38
• 5.10.39
• 5.10.40
• 5.10.41
• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3
• 5.12.4
• 5.12.5
• 5.12.6
• 5.12.7
• 5.12.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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