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Vulnerability record · CVE-2021-3501 · published 6 May 2021

CVE-2021-3501: Linux kernel out-of-bounds write vulnerability

Linux · Linux Kernel

A flaw was found in the Linux kernel in versions before 5.12. The value of internal.ndata, in the KVM API, is mapped to an array index, which can be updated by a user process at anytime which could lead to an out-of-bounds write. The highest threat from this vulnerability is to data integrity and system availability.

7.1 CVSS 3.1 High EPSS 0.38% · top 70.6% CWE-787 · Out-of-bounds write
7.1CVSS 3.1 base score, v2 3.6
0.38%EPSS exploitation probability, 30 days
NoNot in CISA KEV
19Affected product versions listed by NVD
6References
5 Aug 2026Last modified by NVD

Description

A flaw was found in the Linux kernel in versions before 5.12. The value of internal.ndata, in the KVM API, is mapped to an array index, which can be updated by a user process at anytime which could lead to an out-of-bounds write. The highest threat from this vulnerability is to data integrity and system availability.

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

Affected products

19 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://bugzilla.redhat.com/show_bug.cgi?id=1950136 Issue TrackingPatchThird Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=04c4f2ee3f68c9a4bf1653d15f1a9a435ae33f7a Mailing ListPatchVendor Advisory
https://security.netapp.com/advisory/ntap-20210618-0008/ Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1950136 Issue TrackingPatchThird Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=04c4f2ee3f68c9a4bf1653d15f1a9a435ae33f7a Mailing ListPatchVendor Advisory
https://security.netapp.com/advisory/ntap-20210618-0008/ Third Party Advisory

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Source: NIST National Vulnerability Database (record CVE-2021-3501), CISA KEV, FIRST EPSS (scores of 2026-10-05). This page is refreshed as NVD updates the record.