A flaw was found in grub2 when handling split HTTP headers. While processing a split HTTP header, grub2 wrongly advances its control pointer to the internal buffer by one position, which can lead to an out-of-bounds write. This flaw allows an attacker to leverage this issue by crafting a malicious set of HTTP packages making grub2 corrupt its internal memory metadata structure. This leads to data integrity and confidentiality issues or forces grub to crash, resulting in a denial of service attack.

GNU GRUB (aka GRUB2) through 2.12 has a heap-based buffer overflow in fs/hfs.c via crafted sblock data in an HFS filesystem.

A buffer overflow was found in grubfontconstructglyph(). A malicious crafted pf2 font can lead to an overflow when calculating the maxglyphsize value, allocating a smaller than needed buffer for the glyph, this further leads to a buffer overflow and a heap based out-of-bounds write. An attacker may use this vulnerability to circumvent the secure boot mechanism.

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 to the system such as gaining physical access, obtain the ability to alter a pxe-boot network, or have remote access to a networked system with root access. With this access, an attacker could then craft a string to cause a buffer overflow by injecting a malicious payload that leads to arbitrary code execution within GRUB. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A flaw was found in grub2 in versions prior to 2.06. The rmmod implementation allows the unloading of a module used as a dependency without checking if any other dependent module is still loaded leading to a use-after-free scenario. This could allow arbitrary code to be executed or a bypass of Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A flaw was found in grub2 in versions prior to 2.06. Setparamprefix() in the menu rendering code performs a length calculation on the assumption that expressing a quoted single quote will require 3 characters while it actually requires 4 characters which allows an attacker to corrupt memory by one byte for each quote in the input. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A flaw was found in grub2 when handling IPv4 packets. This flaw allows an attacker to craft a malicious packet, triggering an integer underflow in grub code. Consequently, the memory allocation for handling the packet data may be smaller than the size needed. This issue causes an out-of-bands write during packet handling, compromising data integrity, confidentiality issues, a denial of service, and remote code execution.

Grub2: udf: heap based buffer overflow in grubudfreadblock() may lead to arbitrary code execution

Grub2: fs/hfs: integer overflow may lead to heap based out-of-bounds write

A flaw was found in grub2. When reading data from a squash4 filesystem, grub's squash4 fs module uses user-controlled parameters from the filesystem geometry to determine the internal buffer size, however, it improperly checks for integer overflows. A maliciously crafted filesystem may lead some of those buffer size calculations to overflow, causing it to perform a grubmalloc() operation with a smaller size than expected. As a result, the directread() will perform a heap based out-of-bounds write during data reading. This flaw may be leveraged to corrupt grub's internal critical data and may result in arbitrary code execution, by-passing secure boot protections.

A flaw was found in the HFS filesystem. When reading an HFS volume's name at grubfsmount(), the HFS filesystem driver performs a strcpy() using the user-provided volume name as input without properly validating the volume name's length. This issue may read to a heap-based out-of-bounds writer, impacting grub's sensitive data integrity and eventually leading to a secure boot protection bypass.

A Use-After-Free vulnerability has been discovered in GRUB's gettext module. This flaw stems from a programming error where the gettext command remains registered in memory after its module is unloaded. An attacker can exploit this condition by invoking the orphaned command, causing the application to access a memory location that is no longer valid. An attacker could exploit this vulnerability to cause grub to crash, leading to a Denial of Service. Possible data integrity or confidentiality compromise is not discarded.

An out-of-bounds write flaw was found in grub2's NTFS filesystem driver. This issue may allow an attacker to present a specially crafted NTFS filesystem image, leading to grub's heap metadata corruption. In some circumstances, the attack may also corrupt the UEFI firmware heap metadata. As a result, arbitrary code execution and secure boot protection bypass may be achieved.

A use-after-free vulnerability was found on grub2's chainloader command. This flaw allows an attacker to gain access to restricted data or cause arbitrary code execution if they can establish control from grub's memory allocation pattern.

A flaw was found in grub2. The shimlock verifier from grub2 allows non-kernel files to be loaded when secure boot is enabled, giving the possibility of unverified code or modules to be loaded when it should not be allowed.

A flaw was found in grub2. During the network boot process, when trying to search for the configuration file, grub copies data from a user controlled environment variable into an internal buffer using the grubstrcpy() function. During this step, it fails to consider the environment variable length when allocating the internal buffer, resulting in an out-of-bounds write. If correctly exploited, this issue may result in remote code execution through the same network segment grub is searching for the boot information, which can be used to by-pass secure boot protections.

A flaw was found in grub2 in versions prior to 2.06. During USB device initialization, descriptors are read with very little bounds checking and assumes the USB device is providing sane values. If properly exploited, an attacker could trigger memory corruption leading to arbitrary code execution allowing a bypass of the Secure Boot mechanism. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A crafted JPEG image may lead the JPEG reader to underflow its data pointer, allowing user-controlled data to be written in heap. To a successful to be performed the attacker needs to perform some triage over the heap layout and craft an image with a malicious format and payload. This vulnerability can lead to data corruption and eventual code execution or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12.

A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.

A flaw was found in grub2 in versions prior to 2.06, where it incorrectly enables the usage of the ACPI command when Secure Boot is enabled. This flaw allows an attacker with privileged access to craft a Secondary System Description Table (SSDT) containing code to overwrite the Linux kernel lockdown variable content directly into memory. The table is further loaded and executed by the kernel, defeating its Secure Boot lockdown and allowing the attacker to load unsigned code. The highest threat from this vulnerability is to data confidentiality and integrity, as well as system availability.

A flaw was found in grub2 in versions prior to 2.06. The cutmem command does not honor secure boot locking allowing an privileged attacker to remove address ranges from memory creating an opportunity to circumvent SecureBoot protections after proper triage about grub's memory layout. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Redhat: CVE-2022-3775 grub2 - Heap based out-of-bounds write when rendering certain Unicode sequences

An authentication bypass flaw was found in GRUB due to the way that GRUB uses the UUID of a device to search for the configuration file that contains the password hash for the GRUB password protection feature. An attacker capable of attaching an external drive such as a USB stick containing a file system with a duplicate UUID (the same as in the "/boot/" file system) can bypass the GRUB password protection feature on UEFI systems, which enumerate removable drives before non-removable ones. This issue was introduced in a downstream patch in Red Hat's version of grub2 and does not affect the upstream package.

GRUB2 does not call the module fini functions on exit, leading to Debian/Ubuntu's peimage GRUB2 module leaving UEFI system table hooks after exit. This lead to a use-after-free condition, and could possibly lead to secure boot bypass.

GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grubcryptomemcmp and thus allows side-channel attacks.

A flaw was found in grub2. When reading a symbolic link's name from a UFS filesystem, grub2 fails to validate the string length taken as an input. The lack of validation may lead to a heap out-of-bounds write, causing data integrity issues and eventually allowing an attacker to circumvent secure boot protections.

When reading language .mo file in grubmofileopen(), grub2 fails to verify to a integer overflow when allocating its internal buffer. A crafted .mo file may lead to the buffer size calculation to overflow leading to Out-of-bound reads and writes. An attacker may leverage this flaw to leak sensitive data or overwrite critical data possibly leading to the circumvention of secure boot protections.

A flaw was found in grub2. A specially crafted JPEG file can cause the JPEG parser of grub2 to incorrectly check the bounds of its internal buffers, resulting in an out-of-bounds write. The possibility of overwriting sensitive information to bypass secure boot protections is not discarded.

A flaw was found in grub2. The calculation of the translation buffer when reading a language .mo file in grubgettextgetstrfromposition() may overflow, leading to a Out-of-bound write. This issue can be leveraged by an attacker to overwrite grub2's sensitive heap data, eventually leading to the circumvention of secure boot protections.

A flaw was found in grub2. When reading tar files, grub2 allocates an internal buffer for the file name. However, it fails to properly verify the allocation against possible integer overflows. It's possible to cause the allocation length to overflow with a crafted tar file, leading to a heap out-of-bounds write. This flaw eventually allows an attacker to circumvent secure boot protections.