CVE-2021-46952

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.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/2f3380121d49e829fb73ba86240c181bc32ad897	Patch
https://git.kernel.org/stable/c/3d0163821c035040a46d816a42c0780f0f0a30a8	Patch
https://git.kernel.org/stable/c/96fa26b74cdcf9f5c98996bf36bec9fb5b19ffe2	Patch
https://git.kernel.org/stable/c/c09f11ef35955785f92369e25819bf0629df2e59	Patch

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2024-02-27 19:04

Updated : 2024-04-10 20:15

NVD link : CVE-2021-46952

Mitre link : CVE-2021-46952

CVE.ORG link : CVE-2021-46952

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-125

Out-of-bounds Read

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