Detections
Analytics
EulerOS 2.0 SP9 : grub2 (EulerOS-SA-2021-1948)
high Nessus Plugin ID 150176
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 :- 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.(CVE-2020-27779)
- 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.(CVE-2020-14372)
- 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.(CVE-2020-25632)
- A flaw was found in grub2 in versions prior to 2.06.
The option parser allows an attacker to write past the end of a heap-allocated buffer by calling certain commands with a large number of specific short forms of options. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.(CVE-2021-20225)
- A flaw was found in grub2 in versions prior to 2.06.
Setparam_prefix() 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.(CVE-2021-20233)
- A flaw was found in grub2 in versions prior to 2.06.
Variable names present are expanded in the supplied command line into their corresponding variable contents, using a 1kB stack buffer for temporary storage, without sufficient bounds checking. If the function is called with a command line that references a variable with a sufficiently large payload, it is possible to overflow the stack buffer, corrupt the stack frame and control execution which could also circumvent Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.(CVE-2020-27749)
- 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.(CVE-2020-25647)
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
Plugin Details
Severity: High
ID: 150176
File Name: EulerOS_SA-2021-1948.nasl
Version: 1.3
Type: local
Family: Huawei Local Security Checks
Published: 6/3/2021
Updated: 12/28/2023
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: High
Score: 7.3
CVSS v2
Risk Factor: High
Base Score: 7.2
Temporal Score: 5.6
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
CVSS Score Source: CVE-2021-20233
CVSS v3
Risk Factor: High
Base Score: 8.2
Temporal Score: 7.4
Vector: CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Temporal Vector: CVSS:3.0/E:P/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-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 Available: true
Exploit Ease: Exploits are available
Patch Publication Date: 6/2/2021
Reference Information
CVE: CVE-2020-14372, CVE-2020-25632, CVE-2020-25647, CVE-2020-27749, CVE-2020-27779, CVE-2021-20225, CVE-2021-20233