CVE-2023-32282: Intel Processor BIOS Privilege Escalation

CVE-2023-32282 Overview

CVE-2023-32282 is a race condition vulnerability affecting BIOS firmware for certain Intel Processors. This Time-of-Check Time-of-Use (TOCTOU) flaw may allow an already privileged user to potentially escalate their privileges further through local access to the system.

Critical Impact

A privileged attacker with local access can exploit a race condition in BIOS firmware to achieve escalation of privilege, potentially compromising system integrity and availability at the firmware level.

Affected Products

• Intel Processors with vulnerable BIOS firmware (refer to Intel Security Advisory SA-00929 for specific models)
• Systems running affected BIOS firmware versions

Discovery Timeline

• 2024-03-14 - CVE-2023-32282 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2023-32282

Vulnerability Analysis

This vulnerability is classified under CWE-367 (Time-of-Check Time-of-Use Race Condition). The flaw exists within the BIOS firmware of certain Intel Processors where a race condition can be triggered by a privileged user with local access.

The attack requires local access to the system and high privileges to initiate, but the scope is changed (meaning impact extends beyond the vulnerable component). While confidentiality is not directly impacted, the vulnerability poses significant risks to both integrity and availability of the affected system at the firmware level.

Root Cause

The root cause is a Time-of-Check Time-of-Use (TOCTOU) race condition within the Intel BIOS firmware. This type of vulnerability occurs when there is a timing gap between when a security check is performed and when the corresponding resource is used. An attacker can exploit this window to modify the state of the resource after validation but before use, effectively bypassing security controls at the firmware level.

Attack Vector

The attack requires local access to the system and elevated privileges. The attacker must be able to:

1. Gain local access to a system with vulnerable Intel BIOS firmware
2. Execute code with elevated privileges on the target system
3. Trigger the race condition during BIOS operations by precisely timing malicious actions between the security check and resource utilization
4. Successfully exploit the timing window to escalate privileges beyond their current level

Due to the firmware-level nature of this vulnerability, successful exploitation could result in persistent compromise that survives operating system reinstallation. The attack complexity is high due to the precise timing required to win the race condition.

Detection Methods for CVE-2023-32282

Indicators of Compromise

• Unexpected BIOS configuration changes or modifications to firmware settings
• Anomalous system behavior during boot sequences or firmware updates
• Evidence of local privilege escalation attempts targeting firmware components
• Unusual timing patterns in BIOS-related operations indicating race condition exploitation attempts

Detection Strategies

• Monitor for suspicious local access patterns by privileged users targeting firmware interfaces
• Implement firmware integrity monitoring using Trusted Platform Module (TPM) measurements
• Deploy endpoint detection solutions capable of monitoring low-level system interactions
• Review system logs for evidence of repeated BIOS access attempts or timing anomalies

Monitoring Recommendations

• Enable comprehensive logging for all firmware update and BIOS configuration activities
• Utilize SentinelOne's Singularity Platform for endpoint visibility into suspicious privileged operations
• Implement Secure Boot verification to detect unauthorized firmware modifications
• Configure alerts for repeated authentication failures followed by privilege escalation indicators

How to Mitigate CVE-2023-32282

Immediate Actions Required

• Review the Intel Security Advisory SA-00929 to determine if your Intel Processors are affected
• Apply the latest BIOS firmware updates from your system vendor that address this vulnerability
• Restrict local access to affected systems to only essential personnel
• Ensure Secure Boot is enabled to help protect firmware integrity

Patch Information

Intel has released updated BIOS firmware to address this vulnerability. Organizations should consult the Intel Security Advisory SA-00929 for detailed information on affected processors and available firmware updates. Contact your system manufacturer (OEM) for BIOS updates specific to your hardware platform.

Workarounds

• Limit local administrative access to affected systems to reduce the attack surface
• Implement strict access controls and multi-factor authentication for privileged accounts
• Enable BIOS password protection to prevent unauthorized firmware modifications
• Monitor for and investigate any unusual privileged user activity on systems with vulnerable firmware
• Consider physical security measures to limit local access to critical systems until patches are applied