Ubuntu.comUB:CVE-2020-27779CVE-2020-27779
7.5 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
6.9 Medium
CVSS2
Access Vector
LOCAL
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:M/Au:N/C:C/I:C/A:C
0.0004 Low
EPSS
Percentile
5.3%
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.
Notes
| Author | Note |
|---|---|
| sbeattie | grub2-unsigned will contain fixes and supersede grub2, which will contain only BIOS grub bits. |
| OS | Version | Architecture | Package | Version | Filename |
|---|---|---|---|---|---|
| ubuntu | 18.04 | noarch | grub2-signed | < 1.167~18.04.5 | UNKNOWN |
| ubuntu | 20.04 | noarch | grub2-signed | < 1.167.2 | UNKNOWN |
| ubuntu | 20.10 | noarch | grub2-signed | < 1.167.2 | UNKNOWN |
| ubuntu | 21.04 | noarch | grub2-signed | < 1.164 | UNKNOWN |
| ubuntu | 21.10 | noarch | grub2-signed | < 1.169 | UNKNOWN |
| ubuntu | 14.04 | noarch | grub2-signed | < any | UNKNOWN |
| ubuntu | 16.04 | noarch | grub2-signed | < 1.164 | UNKNOWN |
| ubuntu | 18.04 | noarch | grub2-unsigned | < 2.04-1ubuntu44.1.2 | UNKNOWN |
| ubuntu | 20.04 | noarch | grub2-unsigned | < 2.04-1ubuntu44.2 | UNKNOWN |
| ubuntu | 20.10 | noarch | grub2-unsigned | < 2.04-1ubuntu44.2 | UNKNOWN |
Related
7.5 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
6.9 Medium
CVSS2
Access Vector
LOCAL
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:M/Au:N/C:C/I:C/A:C
0.0004 Low
EPSS
Percentile
5.3%