CVE-2022-21131: Intel Core i9-7940x Information Disclosure

CVE-2022-21131 Overview

CVE-2022-21131 is an improper access control vulnerability affecting a wide range of Intel Xeon processors and Intel Core i9 X-series processors. This firmware-level vulnerability allows an authenticated user with local access to potentially enable information disclosure, exposing sensitive data that should otherwise be protected by processor-level access controls.

The vulnerability exists within the processor firmware and represents a significant security concern for enterprise environments, data centers, and high-performance computing systems that rely on Intel Xeon processors for server workloads. Due to the local attack vector requirement, exploitation requires the attacker to already have authenticated access to the target system.

Critical Impact

Authenticated local attackers can bypass processor-level access controls to disclose sensitive information from affected Intel Xeon and Core i9 X-series processors.

Affected Products

• Intel Xeon Scalable Processors (Bronze, Silver, Gold, Platinum families)
• Intel Xeon D-2100 Series Processors
• Intel Core i9-7900X, i9-7920X, i9-7940X, i9-7960X, i9-7980XE Processors

Discovery Timeline

• May 12, 2022 - CVE-2022-21131 published to NVD
• May 5, 2025 - Last updated in NVD database

Technical Details for CVE-2022-21131

Vulnerability Analysis

This vulnerability stems from improper access control mechanisms within the processor firmware of affected Intel Xeon and Core i9 X-series processors. The flaw allows authenticated users with local system access to bypass intended security boundaries and access information that should be protected.

The vulnerability affects multiple generations of Intel server-class processors, including the Xeon Scalable processor family (1st and 2nd generation), Xeon D-2100 series for edge and network applications, and the high-end desktop Core i9 X-series processors. The extensive list of affected processors includes:

• Xeon Bronze series: 3104, 3106, 3204, 3206R
• Xeon Silver series: 4108, 4109T, 4110, 4112, 4114, 4114T, 4116, 4116T, 4208, 4209T, 4210, 4210R, 4210T, 4214, 4214R, 4214Y, 4215, 4215R, 4216
• Xeon Gold series: Multiple variants from 5115 through 6262V
• Xeon Platinum series: 8153 through 9282
• Xeon D-2100 series: D-2123IT through D-2187NT
• Core i9 X-series: 7900X, 7920X, 7940X, 7960X, 7980XE

The information disclosure capability could expose sensitive system data, cryptographic keys, or other protected information residing in processor-accessible memory regions.

Root Cause

The root cause of CVE-2022-21131 is improper access control within the processor firmware. The vulnerability allows authenticated users to access protected information through mechanisms that should enforce stricter access restrictions. This represents a firmware-level security flaw where the processor does not adequately validate or restrict access to certain resources or data structures.

Attack Vector

The attack requires local access to the target system and an authenticated user context. An attacker must first gain access to a system running one of the affected processors, either through legitimate credentials, a compromised user account, or another vulnerability that provides local access.

Once local access is established, the attacker can leverage the improper access control flaw to read sensitive information. The local access requirement means this vulnerability is most likely to be exploited in scenarios such as:

• Multi-tenant cloud or virtualized environments where attackers compromise one tenant and attempt to access data from others
• Insider threat scenarios where authenticated users attempt unauthorized data access
• Post-exploitation scenarios where attackers have established local access and seek to escalate their capabilities

Detection Methods for CVE-2022-21131

Indicators of Compromise

• Unusual access patterns to processor-specific registers or firmware interfaces
• Unexpected system calls or instructions targeting protected memory regions
• Anomalous local user activity attempting to access kernel or firmware-level resources
• Evidence of unauthorized data access or exfiltration following local system compromise

Detection Strategies

• Deploy endpoint detection and response (EDR) solutions to monitor for suspicious local access patterns and privilege escalation attempts
• Implement firmware integrity monitoring to detect unauthorized changes or access attempts
• Monitor system logs for unusual processor-related events or firmware access patterns
• Use hardware-assisted security features and monitoring where available

Monitoring Recommendations

• Enable detailed logging of local user activities, particularly those involving system-level operations
• Implement behavioral analytics to identify anomalous access patterns from authenticated users
• Monitor for attempts to access Model-Specific Registers (MSRs) or other processor-specific interfaces
• Regularly audit user accounts and access privileges to minimize potential attack surface

How to Mitigate CVE-2022-21131

Immediate Actions Required

• Review the Intel Security Advisory SA-00616 for detailed guidance and firmware updates
• Inventory all systems using affected Intel Xeon and Core i9 X-series processors
• Apply firmware updates from Intel and OEM system vendors as they become available
• Implement strict access controls to limit local access to affected systems
• Monitor for suspicious activity from authenticated users on affected systems

Patch Information

Intel has released a security advisory (INTEL-SA-00616) addressing this vulnerability. Organizations should obtain firmware updates through their OEM system vendors (Dell, HP, Lenovo, etc.) or directly from Intel for reference platform implementations. Firmware updates typically require system restarts and should be scheduled during maintenance windows.

The patch addresses the improper access control issue by implementing proper validation and restrictions on access to protected processor resources. Organizations should prioritize patching for systems in high-risk environments such as multi-tenant clouds, financial systems, or those processing sensitive data.

Workarounds

• Restrict local access to affected systems to only essential personnel and services
• Implement network segmentation to limit lateral movement opportunities for attackers
• Deploy additional monitoring and logging for systems that cannot be immediately patched
• Consider migrating critical workloads to patched systems where firmware updates cannot be immediately applied

# Check processor model on Linux systems
cat /proc/cpuinfo | grep -i "model name" | head -1

# Verify current firmware/microcode version
cat /sys/devices/system/cpu/cpu0/microcode/version

# Check system vendor BIOS/firmware version
dmidecode -s bios-version