Vulnerability · Published Mar 8, 2022 · Assigned by redhat
CVE-2021-3981
Low 3.3
In plain English
A low-severity incorrect default permissions in grub2. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | grub2-common | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-aa64 | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-aa64-cdboot | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-aa64-modules | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-ia32 | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-ia32-cdboot | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-ia32-modules | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-x64 | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-x64-cdboot | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-efi-x64-modules | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-pc | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-pc-modules | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-ppc64le | 1:2.02-123.el8_6.8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-ppc64le-modules | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-tools | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-tools-efi | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-tools-extra | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| AlmaLinux:8 | grub2-tools-minimal | 1:2.02-123.el8.alma | ALSA-2022:2110 |
| Debian:12 | grub2 | 2.06-8 | DEBIAN-CVE-2021-3981 |
| Debian:13 | grub2 | 2.06-8 | DEBIAN-CVE-2021-3981 |
| Debian:14 | grub2 | 2.06-8 | DEBIAN-CVE-2021-3981 |
| Rocky Linux:8 | grub2 | 1:2.02-123.el8 | RLSA-2022:2110 |
| Ubuntu:22.04:LTS | grub2-signed | 1.187.3~22.04.1 | USN-6355-1 |
| Ubuntu:22.04:LTS | grub2-signed | 1.187.3~22.04.1 | UBUNTU-CVE-2021-3981 |
| Ubuntu:22.04:LTS | grub2-unsigned | 2.06-2ubuntu14.1 | UBUNTU-CVE-2021-3981 |
| Ubuntu:22.04:LTS | grub2-unsigned | 2.06-2ubuntu14.1 | USN-6355-1 |
| Ubuntu:22.04:LTS | shim | 15.7-0ubuntu1 | USN-6355-1 |
| Ubuntu:22.04:LTS | shim-signed | 1.51.3 | USN-6355-1 |
Affected products (as reported)
Weakness: CWE-276
References
- FEDORA-2021-73d63662b0 vendor-advisory, x_refsource_FEDORA
- https://bugzilla.redhat.com/show_bug.cgi?id=2024170 x_refsource_MISC
- GLSA-202209-12 vendor-advisory, x_refsource_GENTOO
- http://www.openwall.com/lists/oss-security/2024/01/15/3