CVE-2020-15706 Information

Description

GRUB2 contains a race condition in grub_script_function_create() leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing leading to arbitrary code execution and secure boot restriction bypass. This issue affects GRUB2 version 2.04 and prior versions.

CVSS Vector

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

Reference

http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html http://ubuntu.com/security/notices/USN-4432-1 http://www.openwall.com/lists/oss-security/2020/07/29/3 https://access.redhat.com/security/vulnerabilities/grub2bootloader https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011 https://security.netapp.com/advisory/ntap-20200731-0008/ https://usn.ubuntu.com/4432-1/ https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypass https://www.debian.org/security/2020/dsa-4735 https://www.debian.org/security/2020-GRUB-UEFI-SecureBoot https://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/ https://www.openwall.com/lists/oss-security/2020/07/29/3 https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/ https://www.suse.com/support/kb/doc/?id=000019673

Attack Complexity

HIGH

Privileges Required

HIGH

User Interaction Required

HIGH

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

6.4