Description

Integer overflows were discovered in the functions grub_cmd_initrd and grub_initrd_init in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not included in GRUB2 upstream), leading to a heap-based buffer overflow. These could be triggered by an extremely large number of arguments to the initrd command on 32-bit architectures, or a crafted filesystem with very large files on any architecture. An attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. 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

https://www.debian.org/security/2020/dsa-4735

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/msg00017.html

http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html

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

Details

Risk Information

CVSS v2.0

CVSS v3.0