CVE-2021-3981

What it is

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.

At a glance

Exploitability

Can be exploited locally on the machine with a low-privilege account. Limited direct impact.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2022-03-10 17:43 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 04:06 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.3% in the next 30 days (EPSS).
• Severity: 3.3 LOW (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2022-03-10 17:43 UTC

Last modified

2026-06-17 04:06 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-276 · Incorrect default permissions

Record status

Modified

Affected

• Gnu grub2 ≤ 2.06
• Fedoraproject Fedora 34

Attack profile CVSS 3.1 · 3.3

Attack vector

Local

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2021-3981.md and follow it. Check whether this project is affected by CVE-2021-3981. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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