Vulnerability · Published Mar 3, 2021 · Assigned by redhat
CVE-2020-14372
High 7.5
In plain English
A high-severity security flaw in grub2. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.7% (higher than 78% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
A flaw was found in grub2 in versions prior to 2.06, where it incorrectly enables the usage of the ACPI command when Secure Boot is enabled. This flaw allows an attacker with privileged access to craft a Secondary System Description Table (SSDT) containing code to overwrite the Linux kernel lockdown variable content directly into memory. The table is further loaded and executed by the kernel, defeating its Secure Boot lockdown and allowing the attacker to load unsigned code. The highest threat from this vulnerability is to data confidentiality and integrity, as well as system availability.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | shim-aa64 | 15.4-2.el8_1.alma | ALSA-2021:1734 |
| AlmaLinux:8 | shim-ia32 | 15.4-2.el8_1.alma | ALSA-2021:1734 |
| AlmaLinux:8 | shim-unsigned-aarch64 | 15-7.el8_1.alma | ALSA-2021:1734 |
| AlmaLinux:8 | shim-unsigned-x64 | 15.4-4.el8_1.alma | ALSA-2021:1734 |
| AlmaLinux:8 | shim-x64 | 15.4-2.el8_1.alma | ALSA-2021:1734 |
| Alpine:v3.20 | grub | 2.06-r0 | ALPINE-CVE-2020-14372 |
| Alpine:v3.21 | grub | 2.06-r0 | ALPINE-CVE-2020-14372 |
| Alpine:v3.22 | grub | 2.06-r0 | ALPINE-CVE-2020-14372 |
| Alpine:v3.23 | grub | 2.06-r0 | ALPINE-CVE-2020-14372 |
| Alpine:v3.24 | grub | 2.06-r0 | ALPINE-CVE-2020-14372 |
| Debian:12 | grub2 | 2.04-16 | DEBIAN-CVE-2020-14372 |
| Debian:13 | grub2 | 2.04-16 | DEBIAN-CVE-2020-14372 |
| Debian:14 | grub2 | 2.04-16 | DEBIAN-CVE-2020-14372 |
| Rocky Linux:8 | fwupd | 0:1.5.9-1.el8_4 | RLSA-2021:2566 |
| Rocky Linux:8 | shim-unsigned-aarch64 | 0:15-7.el8.1.1 | RLSA-2021:1734 |
Affected products (as reported)
Weakness: CWE-184
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1873150 x_refsource_MISC
- https://access.redhat.com/security/vulnerabilities/RHSB-2021-003 x_refsource_MISC
- https://security.netapp.com/advisory/ntap-20210416-0004/ x_refsource_CONFIRM
- FEDORA-2021-cab258a413 vendor-advisory, x_refsource_FEDORA
- GLSA-202104-05 vendor-advisory, x_refsource_GENTOO