CVE-2021-3981: Low severity centos grub2-pc-modules vulnerability
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.
Other sources
GRUB2 grub.cfg configuration file is created with the wrong permission (0644) allowing unprivileged users to read grub's configuration file content. This presents a low Confidentiality risk as grub.cfg may contain encrypted passwords.
— Red Hat
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is CVE-2021-3981?
CVE-2021-3981 is a vulnerability in grub2 where its configuration file (grub.cfg) is created with the wrong permissions, allowing non-privileged users to read its content.
What is the severity of CVE-2021-3981?
CVE-2021-3981 has a low severity rating.
How can non-privileged users exploit CVE-2021-3981?
Non-privileged users can exploit CVE-2021-3981 by reading the content of the grub.cfg file, which may contain encrypted passwords.
How can I fix CVE-2021-3981?
To fix CVE-2021-3981, update the grub2 package to version 2.06-13 or 2.12~rc1-9, as recommended by Debian.
Where can I find more information about CVE-2021-3981?
You can find more information about CVE-2021-3981 on the MITRE CVE website, the Red Hat security website, and the NIST National Vulnerability Database.