IM
IronMonkey Threat Research

CVE-2020-14372 HIGH

Published: 2021-03-03 | Last Modified: 2024-11-21 | Status: Modified

Description

A flaw was found in grub2 in versions prior to 2.06, where it incorrectly enables the usage of the ACPI command when Secure Boot is enabled. This flaw allows an attacker with privileged access to craft a Secondary System Description Table (SSDT) containing code to overwrite the Linux kernel lockdown variable content directly into memory. The table is further loaded and executed by the kernel, defeating its Secure Boot lockdown and allowing the attacker to load unsigned code. The highest threat from this vulnerability is to data confidentiality and integrity, as well as system availability.

Additional Descriptions (1)

Se encontró un fallo en grub2 en versiones anteriores a 2.06, donde habilita incorrectamente el uso del comando ACPI cuando Secure Boot está habilitado. Este fallo permite a un atacante con acceso privilegiado diseñar un Secondary System Description Table (SSDT) ??que contiene código para sobrescribir el contenido de la variable de bloqueo del kernel de Linux directamente en la memoria. El kernel carga y ejecuta aún más la tabla, anulando su bloqueo de Secure Boot y permite a un atacante cargar código sin firmar. La mayor amenaza de esta vulnerabilidad es la confidencialidad e integridad de los datos, así como la disponibilidad del sistema

CVSS Metrics

Base Score: 7.5 (HIGH)

CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

Attack VectorLOCAL
Attack ComplexityHIGH
Privileges RequiredHIGH
User InteractionNONE
ScopeCHANGED
Confidentiality ImpactHIGH
Integrity ImpactHIGH
Availability ImpactHIGH

Source: [email protected]

Type: Primary

Exploitability Score: 0.8

Impact Score: 6.0

Base Score: 6.2 (MEDIUM)

AV:L/AC:H/Au:N/C:C/I:C/A:C

Access VectorLOCAL
Access ComplexityHIGH
AuthenticationNONE
Confidentiality ImpactCOMPLETE
Integrity ImpactCOMPLETE
Availability ImpactCOMPLETE

Source: [email protected]

Type: Primary

Exploitability Score: 1.9

Impact Score: 10.0

Weaknesses

Source Type Description
[email protected] Secondary
en CWE-184

Affected Products

Vendor Product Version Update Type
gnu grub2 * <built-in method update of dict object at 0x72a9ccf99e80> Application
redhat enterprise_linux 7.0 <built-in method update of dict object at 0x72a9af823d40> Operating System
redhat enterprise_linux 8.0 <built-in method update of dict object at 0x72a9986887c0> Operating System
redhat enterprise_linux_server_aus 7.2 <built-in method update of dict object at 0x72a9af820300> Operating System
redhat enterprise_linux_server_aus 7.3 <built-in method update of dict object at 0x72a9ccf98ac0> Operating System
redhat enterprise_linux_server_aus 7.4 <built-in method update of dict object at 0x72a9ccf99380> Operating System
redhat enterprise_linux_server_aus 7.6 <built-in method update of dict object at 0x72a9cc86f880> Operating System
redhat enterprise_linux_server_aus 7.7 <built-in method update of dict object at 0x72a9cc86fb40> Operating System
redhat enterprise_linux_server_aus 8.2 <built-in method update of dict object at 0x72a9af8224c0> Operating System
redhat enterprise_linux_server_eus 7.6 <built-in method update of dict object at 0x72a9ccf9bb40> Operating System
redhat enterprise_linux_server_eus 7.7 <built-in method update of dict object at 0x72a9b0d8ccc0> Operating System
redhat enterprise_linux_server_eus 8.1 <built-in method update of dict object at 0x72a9af821f40> Operating System
redhat enterprise_linux_server_tus 7.4 <built-in method update of dict object at 0x72a998688940> Operating System
redhat enterprise_linux_server_tus 7.6 <built-in method update of dict object at 0x72a9af823c80> Operating System
redhat enterprise_linux_server_tus 7.7 <built-in method update of dict object at 0x72a9b0d8eb40> Operating System
redhat enterprise_linux_server_tus 8.2 <built-in method update of dict object at 0x72a9af820200> Operating System
redhat enterprise_linux_workstation 7.0 <built-in method update of dict object at 0x72a9af823c00> Operating System
fedoraproject fedora 33 <built-in method update of dict object at 0x72a9b0d8d480> Operating System
fedoraproject fedora 34 <built-in method update of dict object at 0x72a9cc121fc0> Operating System
netapp cloud_backup - <built-in method update of dict object at 0x72a949cf0180> Application
netapp ontap_select_deploy_administration_utility - <built-in method update of dict object at 0x72a949cf1cc0> Application

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:*

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_aus:7.2:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_aus:7.3:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_eus:7.7:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_eus:8.1:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_tus:7.4:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
Yes cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
Yes cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

Operator: OR

Vulnerable CPE
Yes cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
Yes cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*
Notification
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