CVE-2022-29871: Intel CSME Privilege Escalation Flaw

CVE-2022-29871 Overview

CVE-2022-29871 is an improper access control vulnerability affecting the Intel Converged Security Management Engine (CSME) software installer. The vulnerability exists in versions prior to 2239.3.7.0 and allows an authenticated user with local access to potentially escalate privileges on affected systems.

Intel CSME is a critical firmware subsystem that operates independently from the main CPU and handles various security functions including hardware-based security features, remote management capabilities, and platform integrity verification. Due to its low-level nature and extensive hardware access, vulnerabilities in CSME components present significant security risks as they can potentially bypass operating system-level protections.

Critical Impact

An authenticated local attacker can exploit improper access controls in the CSME software installer to escalate privileges, potentially gaining elevated system access on a wide range of Intel platforms including consumer desktops, laptops, and enterprise server systems.

Affected Products

• Intel Converged Security Management Engine Firmware (versions before 2239.3.7.0)
• Intel 8th, 9th, 10th Generation Core processors (i3, i5, i7, i9 series)
• Intel Xeon Scalable processors (Bronze, Silver, Gold, Platinum series)
• Intel Celeron, Pentium, and Atom processors
• Intel 100, 200, 300, 400, 500, 600 series chipsets
• Various Intel motherboard chipsets (B150, B250, B360, B460, B560, B660, Z170, Z270, Z370, Z390, Z490, Z590, Z690, H110, H170, H270, H310, H370, H410, H470, H510, H570, H610, H670, and many more)

Discovery Timeline

• August 11, 2023 - CVE-2022-29871 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2022-29871

Vulnerability Analysis

This vulnerability is classified as an improper access control issue (CWE-284) combined with incorrect authorization (CWE-863). The flaw resides within the Intel CSME software installer component, which is responsible for updating and managing the CSME firmware on Intel platforms.

The vulnerability allows a local authenticated attacker to bypass intended access restrictions during the CSME software installation or update process. Because CSME operates at a level below the operating system with direct hardware access, successful exploitation could allow an attacker to elevate their privileges beyond what should be permitted by standard operating system security controls.

The attack requires local access to the system and an authenticated user session, meaning an attacker would need either physical access or an existing foothold on the target system. While this limits the attack surface compared to remotely exploitable vulnerabilities, the potential impact is significant given CSME's privileged position within the Intel platform architecture.

Root Cause

The root cause of CVE-2022-29871 stems from improper access control mechanisms within the CSME software installer. The installer fails to properly validate and enforce authorization checks, allowing authenticated users to perform operations or access resources that should be restricted to higher-privileged accounts or processes.

This type of vulnerability often occurs when software assumes that authentication alone is sufficient for authorization, or when privilege checks are implemented inconsistently across different code paths within the installer.

Attack Vector

The attack vector for this vulnerability requires local access to an affected system. An attacker who has already gained authenticated access to the system—through legitimate credentials, social engineering, or other means—can leverage this vulnerability to escalate their privileges.

The exploitation scenario involves an authenticated local user interacting with the vulnerable CSME software installer in a way that triggers the improper access control flaw. This could potentially be achieved by manipulating installer parameters, exploiting race conditions during the installation process, or abusing insufficient privilege separation in the installer's operations.

Because the CSME operates at a firmware level with hardware access capabilities, successful privilege escalation through this vector could provide an attacker with persistent access that survives operating system reinstallation, as well as the ability to bypass certain security features that rely on CSME functionality.

Detection Methods for CVE-2022-29871

Indicators of Compromise

• Unexpected CSME firmware version changes or update activities without authorized administrator action
• Unusual process execution patterns related to Intel CSME installer components
• Anomalous privilege escalation events following CSME-related software operations
• Log entries indicating unauthorized access attempts to CSME management interfaces

Detection Strategies

• Monitor system logs for CSME installer execution from non-standard user accounts or unexpected contexts
• Implement endpoint detection rules to alert on privilege escalation chains involving Intel management software components
• Track firmware version changes and validate against authorized update schedules
• Deploy file integrity monitoring on CSME installer binaries and related configuration files

Monitoring Recommendations

• Establish baselines for normal CSME installer activity patterns in your environment
• Configure SIEM rules to correlate local authentication events with subsequent CSME component interactions
• Implement privileged access monitoring for any accounts that legitimately interact with Intel management tools
• Review audit logs regularly for signs of local privilege escalation attempts

How to Mitigate CVE-2022-29871

Immediate Actions Required

• Inventory all systems containing Intel processors and chipsets to identify potentially affected hardware
• Update Intel CSME software installer to version 2239.3.7.0 or later on all affected systems
• Restrict local access to systems to authorized personnel only
• Review and harden access controls for accounts that can interact with firmware management tools

Patch Information

Intel has released updated CSME software installer versions to address this vulnerability. Organizations should update to version 2239.3.7.0 or later. The patch information is available through the Intel Security Advisory SA-00783.

Additionally, NetApp has published a related advisory for their affected products at NetApp Security Advisory NTAP-20230824-0002.

System administrators should coordinate CSME updates through their organization's standard firmware update processes, which may involve BIOS/UEFI updates from system vendors (Dell, HP, Lenovo, etc.) that incorporate the patched Intel components.

Workarounds

• Implement strict least-privilege access controls to limit the number of users with local system access
• Enforce multi-factor authentication for all local and remote access to affected systems
• Segment critical systems to reduce the attack surface available to potential local attackers
• Monitor for and alert on any attempts to execute CSME installer components outside of authorized maintenance windows

# Example: Check current Intel ME/CSME firmware version on Windows
# Run from elevated command prompt
wmic path Win32_PnPEntity where "DeviceID like '%PCI\\VEN_8086%'" get DeviceID,Name | findstr /i "management engine"

# On Linux systems, use Intel MEInfo tool or check via lspci
lspci -v | grep -i "management engine"