CVE-2023-28033 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.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 07/17/2023
The vulnerability identified as CVE-2023-28033 resides within Dell BIOS firmware and represents a critical improper input validation flaw that could enable privilege escalation attacks. This weakness specifically affects the UEFI variable modification process, creating a potential attack vector for adversaries who already possess administrator-level access to a system. The vulnerability stems from insufficient validation of input parameters within the BIOS firmware, allowing malicious actors to manipulate UEFI variables that control system boot behavior and security settings. Such flaws typically arise from inadequate sanitization of user inputs or improper boundary checks during firmware operations, creating opportunities for attackers to inject malicious code or alter system configurations that should remain protected.
The technical exploitation of this vulnerability requires a local authenticated attacker with administrator privileges, which aligns with CWE-20 standards for improper input validation. The UEFI variable modification capability represents a significant security risk because these variables often control critical system functions including secure boot policies, firmware passwords, and boot order configurations. Attackers could potentially leverage this vulnerability to disable secure boot mechanisms, modify boot parameters to load malicious code, or alter system security settings that could persist across reboots. The attack surface is particularly concerning because UEFI variables are typically protected by firmware-level access controls, yet this vulnerability bypasses these protections through inadequate input validation. This type of flaw falls under the ATT&CK technique T1068 which describes "Exploitation for Privilege Escalation" and specifically relates to firmware-level attacks that can bypass traditional operating system security controls.
The operational impact of CVE-2023-28033 extends beyond simple privilege escalation, as it could enable attackers to establish persistent backdoors within system firmware that survive operating system reinstalls or complete system reboots. This persistent nature makes the vulnerability particularly dangerous for enterprise environments where Dell systems are deployed, as attackers could maintain long-term access to critical infrastructure. The vulnerability's local requirement means that physical access or existing administrative credentials are necessary, but this still represents a significant risk in environments where administrative access is compromised or where insider threats exist. Organizations running Dell systems with affected BIOS versions face potential compromise of their entire security posture, as UEFI-level attacks can bypass traditional endpoint protection mechanisms and operating system security controls. The vulnerability affects multiple Dell hardware platforms and could potentially be exploited across various firmware versions, making it a widespread concern for security teams managing Dell infrastructure.
Mitigation strategies for CVE-2023-28033 should prioritize immediate firmware updates from Dell, as these patches typically address the underlying input validation issues that allow UEFI variable manipulation. System administrators should implement strict access controls and monitor for unauthorized UEFI variable modifications, using tools that can detect changes to critical firmware settings. The vulnerability highlights the importance of firmware security monitoring and the need for comprehensive security controls that extend beyond traditional operating system protections. Organizations should also consider implementing firmware integrity monitoring solutions that can detect unauthorized modifications to UEFI variables, as these systems often lack built-in detection mechanisms for firmware-level attacks. Regular security assessments of firmware configurations and access controls should be conducted to identify potential exploitation vectors, and security teams should maintain awareness of emerging firmware-level attack techniques that could exploit similar validation flaws. The vulnerability serves as a reminder that modern security must encompass the entire system stack, including firmware components that traditionally received less attention in security assessments and monitoring programs.