Improper Authorization in grub - CVE-2020-27779
Published: March 3, 2021 / Updated: December 17, 2024
Vulnerability identifier: #VU51194
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2020-27779
CWE-ID: CWE-285
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: GNU
Affected software:
grub
grub
Detailed vulnerability description
The vulnerability allows a local user to bypass authorization checks.
The vulnerability exists within the cutmem command, which does not honor the Secure Boot locking. A local privileged user can remove address ranges from memory creating an opportunity to circumvent Secure Boot protections after proper triage about grub's memory layout.
How to mitigate CVE-2020-27779
Install updates from vendor's repository.