CVE-2021-46952

NFS: fs_context: validate UDP retrans to prevent shift out-of-bounds

Description

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.

Category

7.1
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.02%
Affected: Linux Linux
Affected: Linux Linux
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2021-46952?
CVE-2021-46952 has been scored as a high severity vulnerability.
How to fix CVE-2021-46952?
To fix CVE-2021-46952, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-46952 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-46952 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-46952?
CVE-2021-46952 affects Linux Linux, Linux Linux.
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