^{CVE-2020-5378:}Dell G7 17 7790 BIOS Use-After-Free Vulnerability Allows Local Code Execution in SMM

Overview

This vulnerability affects Dell G7 17 7790 laptops running BIOS versions prior to 1.13.2. The issue is classified as a Use-After-Free vulnerability (CWE-416) in the UEFI BIOS Boot Services. System Management Mode (SMM) is a highly privileged operating mode in x86 processors that provides system-wide functionality like power management and hardware control. Successful exploitation would give an attacker the ability to execute code with SMM privileges, which could lead to:

• Complete system compromise
• Bypassing of security features including secure boot
• Installation of persistent malware that survives operating system reinstallation
• Theft of sensitive information stored in protected memory regions

The vulnerability requires local access to the system memory, which typically means the attacker would need either physical access to the device or the ability to execute code with elevated privileges on the target system.

Remediation

To address this vulnerability, Dell recommends the following actions:

1. Update the system BIOS to version 1.13.2 or later as soon as possible.

   • Visit the Dell Support website (https://www.dell.com/support)
   • Enter your Service Tag or identify your system model
   • Navigate to the Drivers & Downloads section
   • Filter for BIOS updates and download version 1.13.2 or later
   • Follow Dell's instructions for BIOS update installation

2. Additional security measures:

   • Ensure physical security of affected systems
   • Implement proper access controls to prevent unauthorized users from gaining administrative privileges
   • Keep all operating systems and security software up to date
   • Monitor systems for unusual activity that might indicate compromise

References

1. Dell Security Advisory: https://www.dell.com/support/article/SLN322616
2. Common Weakness Enumeration (CWE-416): https://cwe.mitre.org/data/definitions/416.html
3. MITRE CVE Entry: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-5378
4. Dell Support Portal for G7 17 7790: https://www.dell.com/support/home/product-support/product/g-series-17-7790-laptop/