important: grub2/kernel security update
An update for grub2/kernel is now available for NewStart CGSL MAIN 5.04/CGSL CORE 5.04.
NewStart Security has rated this update as having a security impact of important. A Common Vunlnerability Scoring System(CVSS)base score, which gives a detailed severity rating, is available for each vulnerability from the CVElink(s) in the References section.
grub2: The GRand Unified Bootloader (GRUB) is a highly configurable and customizable bootloader with modular architecture. It supports a rich variety of kernel formats, file systems, computer architectures and hardware devices. This subpackage provides tools for support of all platforms.
kernel: This package provides kernel headers and makefiles sufficient to build modules against the kernel package.
grub2: 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.(CVE-2020-10713)
grub2: A flaw was found in current grub2 versions as shipped with Red Hat Enterprise Linux 7 and 8, where the grub memory allocator doesn't check for possible arithmetic overflows on the requested allocation size. This issue leads the function to return invalid memory allocations, causing heap-based overflows in several code paths. The highest threat from this vulnerability is to confidentiality, integrity as well as system availability.(CVE-2020-14308)
grub2: A flaw was found in grub2 while handling symlink on ext filesystems. A filesystem containing a symbolic link with an inode size of UINT32_MAX causes an arithmetic overflow, leading to a zero-sized memory allocation with a subsequent heap-based buffer overflow. The highest threat from this vulnerability is to integrity and system availability.(CVE-2020-14311)
grub2: 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 highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.(CVE-2020-14309)
grub2: A flaw was found in grub2. An expected font value is not verified before proceeding with buffer allocations allowing an attacker to use a malicious font file to create an arithmetic overflow, zero-sized allocation, and further heap-based buffer overflow. The highest threat from this vulnerability is to data integrity and system availability.(CVE-2020-14310)
grub2: 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. This issue affects GRUB2 version 2.04 and prior versions.(CVE-2020-15705)
grub2: 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.(CVE-2020-15706)
grub2: 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.(CVE-2020-15707)
kernel: The iscsi_if_rx() function in 'drivers/scsi/scsi_transport_iscsi.c' in the Linux kernel from v2.6.24-rc1 through 4.13.2 allows local users to cause a denial of service (a system panic) by making a number of certain syscalls by leveraging incorrect length validation in the kernel code.(CVE-2017-14489)
kernel: A flaw was found in the Linux kernel in the way a local user could create keyrings for other users via keyctl commands. This may allow an attacker to set unwanted defaults, a denial of service, or possibly leak keyring information between users.(CVE-2017-18270)
kernel: A vulnerability was found in hiddev_open in drivers/hid/usbhid/hiddev.c in the USB Human Interface Device class subsystem, where an existing device must be validated prior to its access. The device should also ensure the hiddev_list cleanup occurs at failure, as this may lead to a use-after-free problem, or possibly escalate privileges to an unauthorized user.(CVE-2019-19527)
kernel: A flaw was found in the way mremap handled DAX Huge Pages. This flaw allows a local attacker with access to a DAX enabled storage to escalate their privileges on the system.(CVE-2020-10757)
kernel: A flaw was found in the way the mwifiex_cmd_append_vsie_tlv() in Linux kernel's Marvell WiFi-Ex driver handled vendor specific information elements. A local user could use this flaw to escalate their privileges on the system.(CVE-2020-12653)
kernel: A flaw was found in the Linux kernel. The Marvell mwifiex driver allows a remote WiFi access point to trigger a heap-based memory buffer overflow due to an incorrect memcpy operation. The highest threat from this vulnerability is to data integrity and system availability.(CVE-2020-12654)
kernel: A flaw was found in the Linux kernel, where it allows userspace processes, for example, a guest VM, to directly access h/w devices via its VFIO driver modules. The VFIO modules allow users to enable or disable access to the devices' MMIO memory address spaces. If a user attempts to access the read/write devices' MMIO address space when it is disabled, some h/w devices issue an interrupt to the CPU to indicate a fatal error condition, crashing the system. This flaw allows a guest user or process to crash the host system resulting in a denial of service.(CVE-2020-12888)
For details on how to apply this update, which includes the changes described in this advisory, refer to:
Remember the build tag is 5.04.F27B4.