CVE-2021-46952 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Linux	Linux Kernel

Configuration 1 [-]

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

No data.

References

Link	Providers
https://git.kernel.org/stable/c/2f3380121d49e829fb73ba86240c181bc32ad897
https://git.kernel.org/stable/c/3d0163821c035040a46d816a42c0780f0f0a30a8
https://git.kernel.org/stable/c/96fa26b74cdcf9f5c98996bf36bec9fb5b19ffe2
https://git.kernel.org/stable/c/c09f11ef35955785f92369e25819bf0629df2e59
https://lore.kernel.org/linux-cve-announce/20240227184057.2368370-17-gregkh@linuxfoundation.org/T/#u
https://nvd.nist.gov/vuln/detail/CVE-2021-46952
https://www.cve.org/CVERecord?id=CVE-2021-46952

History

Mon, 04 Nov 2024 12:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-02-27T18:40:35.343Z

Updated: 2025-05-04T07:01:04.042Z

Reserved: 2024-02-25T13:45:52.722Z

Link: CVE-2021-46952

Vulnrichment

Updated: 2024-08-04T05:17:43.053Z

NVD

Status : Modified

Published: 2024-02-27T19:04:06.517

Modified: 2024-11-21T06:35:00.973

Link: CVE-2021-46952

Redhat

Severity : Moderate

Publid Date: 2024-02-27T00:00:00Z

Links: CVE-2021-46952 - Bugzilla

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