EulerOS 2.0 SP8 : grub2 (EulerOS-SA-2020-1853)

medium Nessus Plugin ID 139956
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

The remote EulerOS host is missing multiple security updates.

Description

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

- 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.Security Fix(es):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 attacker controlled data.(CVE-2020-14309)There is an issue on grub2 before version 2.06 at function read_section_as_string(). It expects a font name to be at max UINT32_MAX - 1 length in bytes but it doesn't verify it before proceed with buffer allocation to read the value from the font value. An attacker may leverage that by crafting a malicious font file which has a name with UINT32_MAX, leading to read_section_as_string() to an arithmetic overflow, zero-sized allocation and further heap-based buffer overflow.(CVE-2020-14310)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 UINT32_MAX causes an arithmetic overflow leading to a zero-sized memory allocation with subsequent heap-based buffer overflow.(CVE-2020-14311)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)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)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 during the boot process.(CVE-2020-14308)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected grub2 packages.

See Also

http://www.nessus.org/u?544eb392

Plugin Details

Severity: Medium

ID: 139956

File Name: EulerOS_SA-2020-1853.nasl

Version: 1.6

Type: local

Published: 8/28/2020

Updated: 1/6/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

Vector: AV:L/AC:L/Au:N/C:P/I:P/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 6.7

Temporal Score: 5.8

Vector: CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:huawei:euleros:grub2-common, p-cpe:/a:huawei:euleros:grub2-efi-aa64, p-cpe:/a:huawei:euleros:grub2-efi-aa64-cdboot, p-cpe:/a:huawei:euleros:grub2-efi-aa64-modules, p-cpe:/a:huawei:euleros:grub2-tools, p-cpe:/a:huawei:euleros:grub2-tools-extra, p-cpe:/a:huawei:euleros:grub2-tools-minimal, cpe:/o:huawei:euleros:2.0

Required KB Items: Host/local_checks_enabled, Host/EulerOS/release, Host/EulerOS/rpm-list, Host/EulerOS/sp

Excluded KB Items: Host/EulerOS/uvp_version

Exploit Ease: No known exploits are available

Patch Publication Date: 8/28/2020

Reference Information

CVE: CVE-2020-14308, CVE-2020-14309, CVE-2020-14310, CVE-2020-14311, CVE-2020-15706, CVE-2020-15707

IAVA: 2020-A-0349