SB2022101930 - Multiple vulnerabilities in Dell EMC Cloud Tiering Appliance
Published: October 19, 2022
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 7 secuirty vulnerabilities.
1) Security restrictions bypass (CVE-ID: CVE-2020-14372)
The vulnerability allows a local privileged user to bypass implemented security restrictions.
The vulnerability exists due to GRUB enables usage of the acpi command even when Secure Boot is enabled by firmware. A local user with root privileges can put a small SSDT into /boot/efi folder and modify the grub.cfg file to load that SSDT during kernel boot. The SSDT then gets run by the kernel and it overwrites the kernel lock down configuration enabling the attacker to load unsigned kernel modules and kexec unsigned code.
2) Use-after-free (CVE-ID: CVE-2020-25632)
The vulnerability allows a local user to bypass implemented security restrictions.
The vulnerability exists due to a use-after-free error when handling module unloads. A local privileged user can unload a kernel module, trigger a use-after-free error and bypass Secure Boot protection mechanism.
3) Out-of-bounds write (CVE-ID: CVE-2020-25647)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing untrusted input from USB device in grub_usb_device_initialize(). An attacker with physical access to the system can trigger an out-of-bounds write error with a malicious USB drive, bypass Secure Boot protection and execute arbitrary code on the system with elevated privileges.
4) Stack-based buffer overflow (CVE-ID: CVE-2020-27749)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error within the grub_parser_split_cmdline() function while expanding variable names present in the supplied command line in to their corresponding variable contents. A local privileged user can run a specially crafted program to trigger the stack-based buffer overflow and bypass Secure Boot protection.
5) Improper Authorization (CVE-ID: CVE-2020-27779)
The vulnerability allows a local user to bypass authorization checks.
The vulnerability exists within the cutmem command, which does not honor the Secure Boot locking. A local privileged user can remove address ranges from memory creating an opportunity to circumvent Secure Boot protections after proper triage about grub's memory layout.
6) Out-of-bounds write (CVE-ID: CVE-2021-20225)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error within the option parser. A local privileged user can write past the end of a heap-allocated buffer by calling certain commands with a large number of specific short forms of options and execute arbitrary code with elevated privileges.
7) Out-of-bounds write (CVE-ID: CVE-2021-20233)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error within the setparam_prefix() function in menu rendering code. A local privileged user can run a specially crafted program to trigger out-of-bounds write and escalate privileges on the system.
Remediation
Install update from vendor's website.