CVE-2021-46952 - CVE House
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Status published High CVE-2021-46952

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

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

Affected Vendor

Affected Software

Linux
Vulnerable Versions:
9954bf92c0cddd50a2a470be302e1c1ffdf21d42, 5.6, 0, 5.10.36, 5.11.20, 5.12.3, 5.13

Timeline

Official Publish: February 27th, 2024
Last Modified: May 11th, 2026
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.