CVE-2021-3981

Name: CVE-2021-3981
Creator: NVD / NIST
Published: 2022-03-10T17:43:14.77+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

LOWCVSS 3.3/10EPSS 0.31%

Last modified Jun 17, 2026

CVE-2021-3981 is a low-severity vulnerability rated 3.3/10 on the CVSS scale. A flaw in grub2 was found where its configuration file, known as grub.cfg, is being created with the wrong permission set allowing non privileged users to read its content. This represents a low severity confidentiality issue, as those users can eventually read any encrypted passwords present in grub.cfg. EPSS estimates a 0.31% chance of exploitation in the next 30 days.

Description

A flaw in grub2 was found where its configuration file, known as grub.cfg, is being created with the wrong permission set allowing non privileged users to read its content. This represents a low severity confidentiality issue, as those users can eventually read any encrypted passwords present in grub.cfg. This flaw affects grub2 2.06 and previous versions. This issue has been fixed in grub upstream but no version with the fix is currently released.

Metrics

CVSS 3.1

3.3/10

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

EPSS Probability

0.31%

22.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Gnu	Grub2	<= 2.06
Fedoraproject	Fedora	34

References

http://www.openwall.com/lists/oss-security/2024/01/15/3
https://bugzilla.redhat.com/show_bug.cgi?id=2024170Issue Tracking, Patch, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AI776L35DDYPCSAAJPJM3ZEQYSFZHBJX/
https://security.gentoo.org/glsa/202209-12Third Party Advisory
http://www.openwall.com/lists/oss-security/2024/01/15/3
https://bugzilla.redhat.com/show_bug.cgi?id=2024170Issue Tracking, Patch, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AI776L35DDYPCSAAJPJM3ZEQYSFZHBJX/
https://security.gentoo.org/glsa/202209-12Third Party Advisory

Timeline

Published: Mar 10, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-3981?

How severe is CVE-2021-3981?

CVE-2021-3981 has a CVSS score of 3.3/10 (LOW severity). The EPSS model estimates a 0.31% probability of exploitation in the next 30 days.

How do I fix CVE-2021-3981?

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-2021-3981?

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

Scan your code now

Source: NVD / NIST