8.2 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
8 High
AI Score
Confidence
High
7.2 High
CVSS2
Access Vector
LOCAL
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:C/I:C/A:C
0.0004 Low
EPSS
Percentile
13.3%
Máté Kukri discovered that the acpi command in GRUB 2 allowed privileged
users to load crafted ACPI tables when secure boot is enabled. An attacker
could use this to bypass UEFI Secure Boot restrictions. (CVE-2020-14372)
Chris Coulson discovered that the rmmod command in GRUB 2 contained a use-
after-free vulnerability. A local attacker could use this to execute
arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-25632)
Chris Coulson discovered that a buffer overflow existed in the command line
parser in GRUB 2. A local attacker could use this to execute arbitrary code
and bypass UEFI Secure Boot restrictions. (CVE-2020-27749)
It was discovered that the cutmem command in GRUB 2 did not honor secure
boot locking. A local attacker could use this to execute arbitrary code and
bypass UEFI Secure Boot restrictions. (CVE-2020-27779)
It was discovered that the option parser in GRUB 2 contained a heap
overflow vulnerability. A local attacker could use this to execute
arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2021-20225)
It was discovered that the menu rendering implementation in GRUB 2 did not
properly calculate the amount of memory needed in some situations, leading
to out-of-bounds writes. A local attacker could use this to execute
arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2021-20233)
ubuntu.com/security/CVE-2020-14372
ubuntu.com/security/CVE-2020-25632
ubuntu.com/security/CVE-2020-27749
ubuntu.com/security/CVE-2020-27779
ubuntu.com/security/CVE-2021-20225
ubuntu.com/security/CVE-2021-20233
ubuntu.com/security/https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypass2021
ubuntu.com/security/notices/USN-4992-1
8.2 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
8 High
AI Score
Confidence
High
7.2 High
CVSS2
Access Vector
LOCAL
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:C/I:C/A:C
0.0004 Low
EPSS
Percentile
13.3%