CVE-2023-28044 in Dell
Summary
by MITRE • 06/23/2023
Dell BIOS contains an improper input validation vulnerability. A local authenticated malicious user with administrator privileges may potentially exploit this vulnerability in order to modify a UEFI variable.
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Analysis
by VulDB Data Team • 07/18/2023
This vulnerability resides within the Dell BIOS implementation where insufficient input validation mechanisms exist for UEFI variable handling. The flaw allows a locally authenticated attacker with administrator privileges to manipulate UEFI variables through improper validation of input parameters. The vulnerability stems from inadequate sanitization and verification processes that should normally occur when UEFI variables are modified or accessed. According to the Common Weakness Enumeration framework, this represents a weakness categorized under CWE-20, which specifically addresses improper input validation. The attack vector requires local access with administrative credentials, making it a privilege escalation vulnerability rather than a remote exploit.
The technical exploitation of this vulnerability occurs at the UEFI level where system firmware components manage critical boot parameters and security settings. When a malicious user with administrator access attempts to modify UEFI variables, the insufficient validation allows for potentially harmful modifications that could alter system behavior, disable security features, or compromise the integrity of the boot process. The UEFI variable modification capability provides access to fundamental system configuration parameters that control secure boot policies, firmware settings, and hardware initialization sequences. This vulnerability directly impacts the integrity of the Unified Extensible Firmware Interface implementation and undermines the security boundaries that UEFI variables are designed to maintain.
The operational impact of this vulnerability extends beyond simple privilege escalation as it provides attackers with persistent access to core system firmware components. An attacker who successfully exploits this vulnerability could potentially disable security features such as secure boot, modify boot order configurations, or alter firmware settings that control hardware access. The implications are particularly concerning in enterprise environments where Dell systems may be running critical infrastructure applications, as the attacker could establish persistent backdoors or compromise system integrity across multiple boot cycles. This vulnerability aligns with ATT&CK technique T1068 which covers 'Exploitation for Privilege Escalation' and T1542.003 which addresses 'Taint Shared Libraries' through firmware manipulation.
Mitigation strategies for this vulnerability should focus on implementing proper input validation mechanisms within the BIOS firmware code and ensuring that all UEFI variable modifications are properly authenticated and authorized. System administrators should maintain strict access controls and ensure that only authorized personnel have administrator privileges on systems. Firmware updates from Dell should be applied promptly to address this vulnerability, as the fix would involve strengthening input validation routines within the UEFI variable handling code. Additionally, organizations should implement monitoring solutions that can detect unauthorized modifications to UEFI variables and establish baseline configurations that can be used to identify potential tampering. The vulnerability demonstrates the critical importance of firmware security and the need for robust input validation at all levels of system architecture, particularly in the firmware layer where traditional operating system security controls may not apply.