CVE ID:	CVE-2020-15706
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.
Test IDs:	1.3.6.1.4.1.25623.1.1.4.2020.2079.1   1.3.6.1.4.1.25623.1.0.853343   1.3.6.1.4.1.25623.1.1.4.2020.2078.1   1.3.6.1.4.1.25623.1.1.4.2020.2073.1   1.3.6.1.4.1.25623.1.0.704735   1.3.6.1.4.1.25623.1.0.853344   1.3.6.1.4.1.25623.1.1.4.2020.14440.1   1.3.6.1.4.1.25623.1.1.4.2020.2074.1   1.3.6.1.4.1.25623.1.1.4.2020.2077.1
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2020-15706 https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011 https://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/ https://www.openwall.com/lists/oss-security/2020/07/29/3 Debian Security Information: DSA-4735 (Google Search) https://www.debian.org/security/2020/dsa-4735 Debian Security Information: https://www.debian.org/security/2020-GRUB-UEFI-SecureBoot (Google Search) https://www.debian.org/security/2020-GRUB-UEFI-SecureBoot https://security.gentoo.org/glsa/202104-05 http://www.openwall.com/lists/oss-security/2020/07/29/3 RedHat Security Advisories: https://access.redhat.com/security/vulnerabilities/grub2bootloader https://access.redhat.com/security/vulnerabilities/grub2bootloader SuSE Security Announcement: https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/ (Google Search) https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/ SuSE Security Announcement: https://www.suse.com/support/kb/doc/?id=000019673 (Google Search) https://www.suse.com/support/kb/doc/?id=000019673 SuSE Security Announcement: openSUSE-SU-2020:1168 (Google Search) http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html SuSE Security Announcement: openSUSE-SU-2020:1169 (Google Search) http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html https://usn.ubuntu.com/4432-1/ http://ubuntu.com/security/notices/USN-4432-1 https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypass