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

According to the versions of the grub2 packages installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

    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this condition by invoking the orphaned command, causing the application to access a     memory location that is no longer valid.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.(CVE-2025-61662)

    A vulnerability in the GRUB2 bootloader has been identified in the normal module. This flaw, a memory Use     After Free issue, occurs because the normal_exit command is not properly unregistered when its related     module is unloaded. An attacker can exploit this condition by invoking the command after the module has     been removed, causing the system to improperly access a previously freed memory location. This leads to a     system crash or possible impacts in data confidentiality and integrity.(CVE-2025-61664)

    A use-after-free vulnerability has been identified in the GNU GRUB (Grand Unified Bootloader). The flaw     occurs because the file-closing process incorrectly retains a memory pointer, leaving an invalid reference     to a file system structure. 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.(CVE-2025-54771)

    A vulnerability has been identified in the GRUB2 bootloader's normal command that poses an immediate     Denial of Service (DoS) risk. This flaw is a Use-after-Free issue, caused because the normal command is     not properly unregistered when the module is unloaded. An attacker who can execute this command can force     the system to access memory locations that are no longer valid. Successful exploitation leads directly to     system instability, which can result in a complete crash and halt system availability. Impact on the data     integrity and confidentiality is also not discarded.(CVE-2025-61663)

    A vulnerability has been identified in the GRUB (Grand Unified Bootloader) component. This flaw occurs     because the bootloader mishandles string conversion when reading information from a USB device, allowing     an attacker to exploit inconsistent length values. A local attacker can connect a maliciously configured     USB device during the boot sequence to trigger this issue. A successful exploitation may lead GRUB to     crash, leading to a Denial of Service. Data corruption may be also possible, although given the complexity     of the exploit the impact is most likely limited.(CVE-2025-61661)

    GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grub_crypto_memcmp and thus     allows side-channel attacks.(CVE-2024-56738)

Tenable has extracted the preceding description block directly from the EulerOS Virtualization grub2 security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

According to the versions of the grub2 packages installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

    GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grub_crypto_memcmp and thus     allows side-channel attacks.(CVE-2024-56738)

    A flaw was found in grub2. The calculation of the translation buffer when reading a language .mo file in     grub_gettext_getstr_from_position() 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.(CVE-2024-45777)

    When reading data from a hfs filesystem, grub's hfs filesystem module uses user-controlled parameters from     the filesystem metadata to calculate the internal buffers size, however it misses to properly check for     integer overflows. A maliciouly crafted filesystem may lead some of those buffer size calculation to     overflow, causing it to perform a grub_malloc() operation with a smaller size than expected. As a result     the hfsplus_open_compressed_real() function will write past of the internal buffer length. This flaw may     be leveraged to corrupt grub's internal critical data and may result in arbitrary code execution by-     passing secure boot protections.(CVE-2025-1125)

    A flaw was found in grub2. Grub's dump command is not blocked when grub is in lockdown mode, which allows     the user to read any memory information, and an attacker may leverage this in order to extract signatures,     salts, and other sensitive information from the memory.(CVE-2025-1118)

    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     grub_strcpy() 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.(CVE-2025-0624)

    The read command is used to read the keyboard input from the user, while reads it keeps the input length     in a 32-bit integer value which is further used to reallocate the line buffer to accept the next     character. During this process, with a line big enough it's possible to make this variable to overflow     leading to a out-of-bounds write in the heap based buffer. This flaw may be leveraged to corrupt grub's     internal critical data and secure boot bypass is not discarded as consequence.(CVE-2025-0690)     When reading data from disk, the grub's UDF filesystem module utilizes the user controlled data length     metadata to allocate its internal buffers. In certain scenarios, while iterating through disk sectors, it     assumes the read size from the disk is always smaller than the allocated buffer size which is not     guaranteed. A crafted filesystem image may lead to a heap-based buffer overflow resulting in critical data     to be corrupted, resulting in the risk of arbitrary code execution by-passing secure boot     protections.(CVE-2025-0689)

    A flaw was found in grub2. When reading data from a jfs filesystem, grub's jfs filesystem module uses     user-controlled parameters from the filesystem geometry to determine the internal buffer size, however, it     improperly checks for integer overflows. A maliciouly crafted filesystem may lead some of those buffer     size calculations to overflow, causing it to perform a grub_malloc() operation with a smaller size than     expected. As a result, the grub_jfs_lookup_symlink() function will write past the internal buffer length     during grub_jfs_read_file(). This issue can be leveraged to corrupt grub's internal critical data and may     result in arbitrary code execution, by-passing secure boot protections.(CVE-2025-0685)

    A flaw was found in grub2. When performing a symlink lookup from a reiserfs filesystem, grub's reiserfs fs     module uses user-controlled parameters from the filesystem geometry to determine the internal buffer size,     however, it improperly checks for integer overflows. A maliciouly crafted filesystem may lead some of     those buffer size calculations to overflow, causing it to perform a grub_malloc() operation with a smaller     size than expected. As a result, the grub_reiserfs_read_symlink() will call grub_reiserfs_read_real() with     a overflown length parameter, leading to a heap based out-of-bounds write during data reading. This flaw     may be leveraged to corrupt grub's internal critical data and can result in arbitrary code execution, by-     passing secure boot protections.(CVE-2025-0684)

    An integer overflow flaw was found in the BFS file system driver in grub2. When reading a file with an     indirect extent map, grub2 fails to validate the number of extent entries to be read. A crafted or     corrupted BFS filesystem may cause an integer overflow during the file reading, leading to a heap of     bounds read. As a consequence, sensitive data may be leaked, or grub2 will crash.(CVE-2024-45779)

    A flaw was found in grub2. When performing a symlink lookup, the grub's UFS module checks the inode's data     size to allocate the internal buffer to read the file content, however, it fails to check if the symlink     data size has overflown. When this occurs, grub_malloc() may be called with a smaller value than needed.
    When further reading the data from the disk into the buffer, the grub_ufs_lookup_symlink() function will     write past the end of the allocated size. An attack can leverage this by crafting a malicious filesystem,     and as a result, it will corrupt data stored in the heap, allowing for arbitrary code execution used to     by-pass secure boot mechanisms.(CVE-2025-0677)

    A flaw was found in the HFS filesystem. When reading an HFS volume's name at grub_fs_mount(), 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.(CVE-2024-45782)

    A flaw was found in grub2. When performing a symlink lookup from a romfs filesystem, grub's romfs     filesystem 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 grub_malloc() operation     with a smaller size than expected. As a result, the grub_romfs_read_symlink() may cause out-of-bounds     writes when the calling grub_disk_read() function. This issue may be leveraged to corrupt grub's internal     critical data and can result in arbitrary code execution by-passing secure boot     protections.(CVE-2025-0686)

    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 grub_malloc() operation with a smaller size than     expected. As a result, the direct_read() 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.(CVE-2025-0678)

    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.(CVE-2024-45780)

    A stack overflow flaw was found when reading a BFS file system. A crafted BFS filesystem may lead to an     uncontrolled loop, causing grub2 to crash.(CVE-2024-45778)

    A flaw was found in grub2 where the grub_extcmd_dispatcher() function calls grub_arg_list_alloc() to     allocate memory for the grub's argument list. However, it fails to check in case the memory allocation     fails. Once the allocation fails, a NULL point will be processed by the parse_option() function, leading     grub to crash or, in some rare scenarios, corrupt the IVT data.(CVE-2024-45775)

    When reading the language .mo file in grub_mofile_open(), grub2 fails to verify an integer overflow when     allocating its internal buffer. A crafted .mo file may lead the buffer size calculation to overflow,     leading to out-of-bound reads and writes. This flaw allows an attacker to leak sensitive data or overwrite     critical data, possibly circumventing secure boot protections.(CVE-2024-45776)

    A flaw was found in grub2. When failing to mount an HFS+ grub, the hfsplus filesystem driver doesn't     properly set an ERRNO value. This issue may lead to a NULL pointer access.(CVE-2024-45783)

    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.(CVE-2024-45774)

    A flaw was found in command/gpg. In some scenarios, hooks created by loaded modules are not removed when     the related module is unloaded. This flaw allows an attacker to force grub2 to call the hooks once the     module that registered it was unloaded, leading to a use-after-free vulnerability. If correctly exploited,     this vulnerability may result in arbitrary code execution, eventually allowing the attacker to bypass     secure boot protections.(CVE-2025-0622)

    grub2 allowed attackers with access to the grub shell to access files on the encrypted     disks.(CVE-2024-49504)

    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.(CVE-2024-56737)

    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.(CVE-2024-45781)

Tenable has extracted the preceding description block directly from the EulerOS Virtualization grub2 security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLES16 / SLES_SAP16 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2025:21212-1 advisory.

    Changes in grub2:

    - CVE-2025-54771: Fixed grub_file_close() does not properly controls the fs refcount (bsc#1252931)
    - CVE-2025-54770: Fixed missing unregister call for net_set_vlan command may lead to use-after-free     (bsc#1252930)
    - CVE-2025-61662: Fixed missing unregister call for gettext command may lead to use-after-free     (bsc#1252933)
    - CVE-2025-61663: Fixed missing unregister call for normal commands may lead to use-after-free     (bsc#1252934)
    - CVE-2025-61664: Fixed missing unregister call for normal_exit command may lead to use-after-free     (bsc#1252935)
    - CVE-2025-61661: Fixed out-of-bounds write in grub_usb_get_string() function (bsc#1252932)

    - Bump upstream SBAT generation to 6

    - Fix sparse file not allowed error after grub2-reboot (bsc#1245738)
    - Fix PowerPC network boot prefix to correctly locate grub.cfg (bsc#1249385)
    - turn off page flipping for i386-pc using VBE video backend (bsc#1245636)
    - Fix boot hangs in setting up serial console when ACPI SPCR table is present       and redirection is disabled (bsc#1249088)
    - Fix timeout when loading initrd via http after PPC CAS reboot (bsc#1245953)
    - Skip mount point in grub_find_device function (bsc#1246231)

    - CVE-2024-56738: Fixed side-channel attack due to not constant-time algorithm in grub_crypto_memcmp     (bsc#1234959)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

According to the versions of the grub2 packages installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

    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.(CVE-2024-56737)

    GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grub_crypto_memcmp and thus     allows side-channel attacks.(CVE-2024-56738)

Tenable has extracted the preceding description block directly from the EulerOS Virtualization grub2 security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote openSUSE 16 host has packages installed that are affected by multiple vulnerabilities as referenced in the openSUSE-SU-2025:20163-1 advisory.

    Changes in grub2:

    - CVE-2025-54771: Fixed grub_file_close() does not properly controls the fs refcount (bsc#1252931)
    - CVE-2025-54770: Fixed missing unregister call for net_set_vlan command may lead to use-after-free     (bsc#1252930)
    - CVE-2025-61662: Fixed missing unregister call for gettext command may lead to use-after-free     (bsc#1252933)
    - CVE-2025-61663: Fixed missing unregister call for normal commands may lead to use-after-free     (bsc#1252934)
    - CVE-2025-61664: Fixed missing unregister call for normal_exit command may lead to use-after-free     (bsc#1252935)
    - CVE-2025-61661: Fixed out-of-bounds write in grub_usb_get_string() function (bsc#1252932)

    - Bump upstream SBAT generation to 6

    - Fix sparse file not allowed error after grub2-reboot (bsc#1245738)
    - Fix PowerPC network boot prefix to correctly locate grub.cfg (bsc#1249385)
    - turn off page flipping for i386-pc using VBE video backend (bsc#1245636)
    - Fix boot hangs in setting up serial console when ACPI SPCR table is present       and redirection is disabled (bsc#1249088)
    - Fix timeout when loading initrd via http after PPC CAS reboot (bsc#1245953)
    - Skip mount point in grub_find_device function (bsc#1246231)

    - CVE-2024-56738: Fixed side-channel attack due to not constant-time algorithm in grub_crypto_memcmp     (bsc#1234959)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

According to the versions of the grub2 packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

    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.(CVE-2024-56737)

    GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grub_crypto_memcmp and thus     allows side-channel attacks.(CVE-2024-56738)

Tenable has extracted the preceding description block directly from the EulerOS grub2 security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

According to the versions of the grub2 packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

    GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grub_crypto_memcmp and thus     allows side-channel attacks.(CVE-2024-56738)

Tenable has extracted the preceding description block directly from the EulerOS grub2 security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2025:02813-1 advisory.

    - CVE-2024-56738: Fixed side-channel attack due to not       constant-time algorithm in grub_crypto_memcmp (bsc#1234959)

    Other fixes:
    - Fix test -f and -s do not work properly over the network files       served via tftp and http (bsc#1246157, bsc#1246237)
    - Skip mount point in grub_find_device function (bsc#1246231)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2025:02772-1 advisory.

    - CVE-2024-56738: Fixed side-channel attack due to not       constant-time algorithm in grub_crypto_memcmp (bsc#1234959)

    Other fixes:
    - Fix test -f and -s do not work properly over the network files       served via tftp and http (bsc#1246157, bsc#1246237)
    - Skip mount point in grub_find_device function (bsc#1246231)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLES12 host has packages installed that are affected by a vulnerability as referenced in the SUSE- SU-2025:02725-1 advisory.

    - CVE-2024-56738: Fixed side-channel attack due to not constant-time algorithm in grub_crypto_memcmp     (bsc#1234959)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grub_crypto_memcmp and thus     allows side-channel attacks. (CVE-2024-56738)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Severity
302672	EulerOS Virtualization 2.12.0 : grub2 (EulerOS-SA-2026-1486)	Nessus	Huawei Local Security Checks	high
302662	EulerOS Virtualization 2.12.1 : grub2 (EulerOS-SA-2026-1429)	Nessus	Huawei Local Security Checks	high
297328	EulerOS Virtualization 2.10.1 : grub2 (EulerOS-SA-2026-1119)	Nessus	Huawei Local Security Checks	high
297299	EulerOS Virtualization 2.10.0 : grub2 (EulerOS-SA-2026-1170)	Nessus	Huawei Local Security Checks	high
279373	SUSE SLES16: grub2 / grub2-arm64-efi / grub2-common / grub2-i386-pc / etc (SUSE-SU-2025:21212-1)	Nessus	SuSE Local Security Checks	high
279305	EulerOS Virtualization 2.13.1 : grub2 (EulerOS-SA-2025-2542)	Nessus	Huawei Local Security Checks	high
279289	EulerOS Virtualization 2.13.0 : grub2 (EulerOS-SA-2025-2577)	Nessus	Huawei Local Security Checks	high
279059	openSUSE 16 Security Update : grub2 (openSUSE-SU-2025:20163-1)	Nessus	SuSE Local Security Checks	high
271339	EulerOS 2.0 SP13 : grub2 (EulerOS-SA-2025-2261)	Nessus	Huawei Local Security Checks	high
271332	EulerOS 2.0 SP13 : grub2 (EulerOS-SA-2025-2293)	Nessus	Huawei Local Security Checks	high
270057	EulerOS 2.0 SP11 : grub2 (EulerOS-SA-2025-2227)	Nessus	Huawei Local Security Checks	medium
270054	EulerOS 2.0 SP11 : grub2 (EulerOS-SA-2025-2195)	Nessus	Huawei Local Security Checks	medium
264443	EulerOS 2.0 SP12 : grub2 (EulerOS-SA-2025-2009)	Nessus	Huawei Local Security Checks	medium
264424	EulerOS 2.0 SP10 : grub2 (EulerOS-SA-2025-2098)	Nessus	Huawei Local Security Checks	medium
264391	EulerOS 2.0 SP12 : grub2 (EulerOS-SA-2025-2040)	Nessus	Huawei Local Security Checks	medium
261865	EulerOS 2.0 SP10 : grub2 (EulerOS-SA-2025-2070)	Nessus	Huawei Local Security Checks	medium
250303	SUSE SLED15: grub2 / grub2-arm64-efi / grub2-i386-pc / grub2-powerpc-ieee1275 / etc (SUSE-SU-2025:02813-1)	Nessus	SuSE Local Security Checks	medium
249222	SUSE SLED15: grub2 / grub2-arm64-efi / grub2-arm64-efi-debug / etc (SUSE-SU-2025:02772-1)	Nessus	SuSE Local Security Checks	medium
245588	SUSE SLES12: grub2 / grub2-i386-pc / grub2-snapper-plugin / etc (SUSE-SU-2025:02725-1)	Nessus	SuSE Local Security Checks	medium
231890	Linux Distros Unpatched Vulnerability : CVE-2024-56738	Nessus	Misc.	medium

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