Linux Kernel up to 5.10.35/5.11.19/5.12.2 NFS xprt_calc_majortimeo out-of-bounds

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.10.35/5.11.19/5.12.2. It has been classified as problematic. Affected by this issue is the function xprt_calc_majortimeo of the component NFS. This manipulation causes out-of-bounds. The identification of this vulnerability is CVE-2021-46952. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.10.35/5.11.19/5.12.2 (Operating System). It has been declared as problematic. Affected by this vulnerability is the function xprt_calc_majortimeo of the component NFS. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: NFS: fs_context: validate UDP retrans to prevent shift out-of-bounds Fix shift out-of-bounds in xprt_calc_majortimeo(). This is caused by a garbage timeout (retrans) mount option being passed to nfs mount, in this case from syzkaller. If the protocol is XPRT_TRANSPORT_UDP, then 'retrans' is a shift value for a 64-bit long integer, so 'retrans' cannot be >= 64. If it is >= 64, fail the mount and return an error.

The weakness was shared 02/27/2024. It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2021-46952 since 02/25/2024. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 5.10.36, 5.11.20, 5.12.3 or 5.13 eliminates this vulnerability. Applying the patch 96fa26b74cdc/2f3380121d49/3d0163821c03/c09f11ef3595 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.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 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
• 5.11.0
• 5.11.1
• 5.11.2
• 5.11.3
• 5.11.4
• 5.11.5
• 5.11.6
• 5.11.7
• 5.11.8
• 5.11.9
• 5.11.10
• 5.11.11
• 5.11.12
• 5.11.13
• 5.11.14
• 5.11.15
• 5.11.16
• 5.11.17
• 5.11.18
• 5.11.19
• 5.12.0
• 5.12.1
• 5.12.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

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CPE 2.2info

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