CVE-2020-27779 is a high-severity flaw in GRUB2 versions prior to 2.06, affecting products from Fedora Project, GNU, NetApp, and Red Hat. This vulnerability allows a highly privileged attacker to bypass Secure Boot protections by manipulating memory ranges using the cutmem command. The attack requires high privileges and complexity, but can lead to significant impacts on data confidentiality, integrity, and system availability. There is no evidence of active exploitation, nor are there publicly available exploit tools like Metasploit or ExploitDB, though it has received some community discussion and media coverage.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 2.06CPE matchmatch criteria | cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:* | ||
7.0CPE matchmatch criteria | cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* | ||
8.0CPE matchmatch criteria | cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* | ||
7.2CPE matchmatch criteria | cpe:2.3:o:redhat:enterprise_linux_server_aus:7.2:*:*:*:*:*:*:* | ||
7.3CPE matchmatch criteria | cpe:2.3:o:redhat:enterprise_linux_server_aus:7.3:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.3 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.
The average CVE in this peer group has 0.2 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
A flaw was found in grub2 in versions prior to 2.06. The cutmem command does not honor secure boot locking allowing an privileged attacker to remove address ranges from memory creating an opportunity to circumvent SecureBoot protections after proper triage about grub's memory layout. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Mar 9, 2021grub2: cutmem command allows privileged user to remove memory regions when Secure Boot is enabled
Mar 2, 2021