USN-4432-1 grub2, grub2-signed vulnerabilities

Jesse Michael and Mickey Shkatov discovered that the configuration parser in GRUB2 did not properly exit when errors were discovered, resulting in heap-based buffer overflows. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. CVE-2020-10713 Chris...

grub2: Use-after-free redefining a function whilst the same function is already executing

GRUB2 contains a race condition in grubscriptfunctioncreate 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...

grub2: Fail kernel validation without shim protocol

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...

grub2: Integer overflow in grub_squash_read_symlink may lead to heap-based buffer overflow

A flaw was found in grub2. When handling squashfs filesystems containing a symbolic link with name length of UINT32 bytes in size, the name size leads to an arithmetic overflow leading to a zero-size allocation further causing a heap-based buffer overflow with attacker controlled data. The highes...

grub2: Crafted grub.cfg file can lead to arbitrary code execution during boot process

A flaw was found in grub2, prior to version 2.06. An attacker may use the GRUB 2 flaw to hijack and tamper the GRUB verification process. This flaw also allows the bypass of Secure Boot protections. In order to load an untrusted or modified kernel, an attacker would first need to establish access...

grub2: Integer overflow in initrd size handling

Integer overflows were discovered in the functions grubcmdinitrd and grubinitrdinit 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...

ALPINE-CVE-2020-15705

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...

ALPINE-CVE-2020-15706

GRUB2 contains a race condition in grubscriptfunctioncreate 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...

DEBIAN-CVE-2020-15707

Integer overflows were discovered in the functions grubcmdinitrd and grubinitrdinit 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...

ALPINE-CVE-2020-15707

Integer overflows were discovered in the functions grubcmdinitrd and grubinitrdinit 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...

DEBIAN-CVE-2020-15706

GRUB2 contains a race condition in grubscriptfunctioncreate 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...

SUSE-SU-2020:14440-1 Security update for grub2

This update for grub2 fixes the following issues: - Fix for CVE-2020-10713 bsc1168994 - Fix for CVE-2020-14308 CVE-2020-14309, CVE-2020-14310, CVE-2020-14311 bsc1173812 - Fix for CVE-2020-15706 bsc1174463 - Fix for CVE-2020-15707 bsc1174570 - Fix packed-not-aligned error on GCC 8 bsc1084632...

UBUNTU-CVE-2020-15707

Integer overflows were discovered in the functions grubcmdinitrd and grubinitrdinit 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...

UBUNTU-CVE-2020-15705

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...

UBUNTU-CVE-2020-14308

In grub2 versions before 2.06 the grub memory allocator doesn't check for possible arithmetic overflows on the requested allocation size. This leads the function to return invalid memory allocations which can be further used to cause possible integrity, confidentiality and availability impacts...

UBUNTU-CVE-2020-14309

There's an issue with grub2 in all versions before 2.06 when handling squashfs filesystems containing a symbolic link with name length of UINT32 bytes in size. The name size leads to an arithmetic overflow leading to a zero-size allocation further causing a heap-based buffer overflow with attacke...

UBUNTU-CVE-2020-15706

GRUB2 contains a race condition in grubscriptfunctioncreate 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...

UBUNTU-CVE-2020-10713

A flaw was found in grub2, prior to version 2.06. An attacker may use the GRUB 2 flaw to hijack and tamper the GRUB verification process. This flaw also allows the bypass of Secure Boot protections. In order to load an untrusted or modified kernel, an attacker would first need to establish access...

UBUNTU-CVE-2020-14311

There is an issue with grub2 before version 2.06 while handling symlink on ext filesystems. A filesystem containing a symbolic link with an inode size of UINT32MAX causes an arithmetic overflow leading to a zero-sized memory allocation with subsequent heap-based buffer overflow...

Microsoft Guidance for Addressing Security Feature Bypass in GRUB

Executive Summary Microsoft is aware of a vulnerability in the GRand Unified Boot Loader GRUB, commonly used by Linux. This vulnerability, known as “There’s a Hole in the Boot”, could allow for Secure Boot bypass. To exploit this vulnerability, an attacker would need to have administrative...