CVE-2021-21574 : Exploit Details and Defense Strategies

Dell BIOSConnect feature in certain versions of Dell BIOS has a critical buffer overflow vulnerability that could be exploited by a malicious admin user to execute arbitrary code and bypass UEFI restrictions.

Understanding CVE-2021-21574

This section covers the details and impact of the CVE-2021-21574 vulnerability.

What is CVE-2021-21574?

The CVE-2021-21574 vulnerability is a buffer overflow issue present in Dell BIOSConnect, allowing an authenticated admin user to potentially run arbitrary code on the system with elevated privileges.

The Impact of CVE-2021-21574

The impact of this vulnerability is rated as HIGH according to the CVSS v3.1 base score, potentially leading to unauthorized code execution and bypassing of UEFI restrictions.

Technical Details of CVE-2021-21574

This section outlines the technical aspects of the CVE-2021-21574 vulnerability.

Vulnerability Description

The vulnerability is classified as a stack-based buffer overflow (CWE-121), presenting a serious risk to affected systems.

Affected Systems and Versions

Dell BIOSConnect in certain unspecified versions, specifically those less than Gen 11 and Gen 10, is impacted by this vulnerability.

Exploitation Mechanism

An authenticated admin user with local access can exploit this vulnerability to execute arbitrary code, potentially leading to privilege escalation.

Mitigation and Prevention

To safeguard systems from CVE-2021-21574, immediate actions and long-term security practices are crucial.

Immediate Steps to Take

It is recommended to apply vendor-supplied patches and updates promptly to mitigate the risk of exploitation.

Long-Term Security Practices

Implement strict access controls, regularly monitor system integrity, and educate users on best security practices to prevent unauthorized access and exploitation.

Patching and Updates

Stay informed about security advisories from Dell and promptly apply recommended patches and updates to address known vulnerabilities.