CVE-2020-15705

medium

Description

GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed. This only affects systems where the kernel signing certificate has been imported directly into the secure boot database and the GRUB image is booted directly without the use of shim. This issue affects GRUB2 version 2.04 and prior versions.

References

https://www.suse.com/support/kb/doc/?id=000019673

http://ubuntu.com/security/notices/USN-4432-1

https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html

https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypass

https://www.debian.org/security/2020-GRUB-UEFI-SecureBoot

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011

https://access.redhat.com/security/vulnerabilities/grub2bootloader

https://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/

https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/

https://www.openwall.com/lists/oss-security/2020/07/29/3

http://www.openwall.com/lists/oss-security/2020/07/29/3

https://security.netapp.com/advisory/ntap-20200731-0008/

https://usn.ubuntu.com/4432-1/

http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00067.html

http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00069.html

http://www.openwall.com/lists/oss-security/2021/03/02/3

https://security.gentoo.org/glsa/202104-05

http://www.openwall.com/lists/oss-security/2021/09/17/2

http://www.openwall.com/lists/oss-security/2021/09/17/4

http://www.openwall.com/lists/oss-security/2021/09/21/1

Details

Source: MITRE

Published: 2020-07-29

Updated: 2022-04-18

Type: CWE-347

Risk Information

CVSS v2

Base Score: 4.4

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

Impact Score: 6.4

Exploitability Score: 3.4

Severity: MEDIUM

CVSS v3

Base Score: 6.4

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

Impact Score: 5.9

Exploitability Score: 0.5

Severity: MEDIUM