CVE-2021-3418

If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.

CVSS v3 6.4 MEDIUM
CVSS v2.0 4.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.5 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

4.4^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:M/Au:N/C:P/I:P/A:P

Exploitability : 3.4 / Impact : 6.4

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=1933757	Issue Tracking Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1933757	Issue Tracking Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:*

History

21 Nov 2024, 06:21

Type	Values Removed	Values Added
References	~~() https://bugzilla.redhat.com/show_bug.cgi?id=1933757 - Issue Tracking, Third Party Advisory~~	() https://bugzilla.redhat.com/show_bug.cgi?id=1933757 - Issue Tracking, Third Party Advisory

Information

Published : 2021-03-15 22:15

Updated : 2024-11-21 06:21

NVD link : CVE-2021-3418

Mitre link : CVE-2021-3418

CVE.ORG link : CVE-2021-3418

JSON object : View

Products Affected

gnu

grub2

CWE

CWE-281

Improper Preservation of Permissions

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