CVE-2021-20268

Name: CVE-2021-20268
Creator: NVD / NIST
Published: 2021-03-09T18:15:15.687+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 0.32%

Last modified Jun 17, 2026

CVE-2021-20268 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. An out-of-bounds access flaw was found in the Linux kernel's implementation of the eBPF code verifier in the way a user running the eBPF script calls dev_map_init_map or sock_map_alloc. This flaw allows a local user to crash the system or possibly escalate their privileges. EPSS estimates a 0.32% chance of exploitation in the next 30 days.

Description

An out-of-bounds access flaw was found in the Linux kernel's implementation of the eBPF code verifier in the way a user running the eBPF script calls dev_map_init_map or sock_map_alloc. This flaw allows a local user to crash the system or possibly escalate their privileges. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Metrics

CVSS 3.1

7.8/10

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

EPSS Probability

0.32%

23.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	< 5.10.10

References

https://bugzilla.redhat.com/show_bug.cgi?id=1923816Issue Tracking, Patch, Third Party Advisory
https://lore.kernel.org/bpf/CACAyw99bEYWJCSGqfLiJ9Jp5YE1ZsZSiJxb4RFUTwbofipf0dA%40mail.gmail.com/T/#m8929643e99bea9c18ed490a7bc2591145eac6444
https://security.netapp.com/advisory/ntap-20210409-0006/Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1923816Issue Tracking, Patch, Third Party Advisory
https://lore.kernel.org/bpf/CACAyw99bEYWJCSGqfLiJ9Jp5YE1ZsZSiJxb4RFUTwbofipf0dA%40mail.gmail.com/T/#m8929643e99bea9c18ed490a7bc2591145eac6444
https://security.netapp.com/advisory/ntap-20210409-0006/Third Party Advisory

Timeline

Published: Mar 9, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20268?

How severe is CVE-2021-20268?

CVE-2021-20268 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.32% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20268?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20268?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST