CVE-2022-27879: Intel Pentium J6426 Info Disclosure Flaw

CVE-2022-27879 Overview

CVE-2022-27879 is an improper buffer restrictions vulnerability in the BIOS firmware for various Intel Processors. This firmware-level vulnerability allows a privileged user with local access to potentially enable information disclosure by exploiting improper buffer handling within the BIOS. The vulnerability affects a wide range of Intel processor families including Pentium, Celeron, Atom, and Pentium Silver series, making it relevant to numerous embedded systems, low-power devices, and consumer computing platforms.

Critical Impact

A privileged attacker with local system access can exploit improper buffer restrictions in the BIOS firmware to potentially disclose sensitive information from memory regions that should be protected.

Affected Products

• Intel Pentium J-series processors (J6426, J4205, J3710, J2900, J2850) and associated firmware
• Intel Pentium N-series processors (N6415, N4200, N4200E, N3710, N3700, N3540, N3530, N3520, N3510) and associated firmware
• Intel Celeron J-series processors (J6412, J6413, J4025, J4125, J3355, J3455, J3060, J3160, J1800, J1900, J1750, J1850) and associated firmware
• Intel Celeron N-series processors (N6210, N6211, N4500, N4505, N5100, N5105, N4020, N4120, N3350, N3450, N3010, N3060, N3160, N3000, N3050, N3150, N2xxx series) and associated firmware
• Intel Atom X5-E3930, X5-E3940, X7-E3950 processors and associated firmware
• Intel Pentium Silver processors (N6000, N6005, J5040, N5030, J5005, N5000) and associated firmware

Discovery Timeline

• August 11, 2023 - CVE-2022-27879 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2022-27879

Vulnerability Analysis

This vulnerability stems from improper buffer restrictions within the BIOS firmware of affected Intel processors. BIOS firmware operates at the lowest level of the system stack, executing before the operating system loads and having direct access to hardware resources. When buffer boundaries are not properly enforced in this privileged context, an attacker who has already gained elevated local access can manipulate buffer operations to read data from unintended memory regions.

The weakness classification includes CWE-92 (BIOS Improperly Restricts Critical Operations) and CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), indicating that the vulnerability lies in how the BIOS handles memory operations and enforces access controls to critical system functions.

Root Cause

The root cause is improper buffer restrictions in the BIOS firmware code. When processing certain operations, the BIOS fails to adequately validate or restrict buffer boundaries, allowing data to be read from or written to memory locations beyond the intended buffer. This is a classic firmware-level memory safety issue where boundary checks are either missing, incomplete, or implemented incorrectly. Given that BIOS firmware executes with the highest system privileges and before operating system security controls are active, such flaws can bypass traditional OS-level protections.

Attack Vector

The attack vector requires local access and high privileges to exploit. An attacker would need to:

1. Gain administrative or root-level access to a system containing an affected Intel processor
2. Interact with the BIOS firmware through available interfaces (such as firmware update mechanisms, System Management Mode, or UEFI runtime services)
3. Craft inputs that exploit the improper buffer restrictions to cause the BIOS to disclose contents of protected memory regions
4. Extract sensitive information such as cryptographic keys, authentication credentials, or other confidential data stored in protected firmware memory areas

Since this is a firmware-level vulnerability, exploitation techniques would involve low-level system interactions and potentially require specialized tools to interface with BIOS/UEFI components at runtime.

Detection Methods for CVE-2022-27879

Indicators of Compromise

• Unexpected BIOS/UEFI firmware access patterns or attempts to invoke firmware services from privileged processes
• Anomalous System Management Interrupt (SMI) activity that could indicate exploitation attempts
• Unusual memory access patterns in regions typically protected by the firmware
• Evidence of privilege escalation attempts followed by firmware interface interactions

Detection Strategies

• Deploy endpoint detection solutions capable of monitoring firmware-level activities and BIOS interactions
• Implement hardware-based security monitoring using Intel Platform Trust Technology (PTT) or Trusted Platform Module (TPM) measurements to detect firmware integrity violations
• Monitor for attempts to access firmware update interfaces or UEFI runtime services from unexpected processes
• Utilize SentinelOne's behavioral AI to detect anomalous local privilege escalation chains that may precede firmware exploitation

Monitoring Recommendations

• Enable firmware attestation and integrity verification during system boot using secure boot mechanisms
• Implement continuous monitoring of privileged process behavior for signs of firmware interaction
• Maintain audit logs of all BIOS/UEFI configuration changes and firmware updates
• Deploy hardware security module (HSM) based solutions to protect sensitive credentials from firmware-level attacks

How to Mitigate CVE-2022-27879

Immediate Actions Required

• Identify all systems containing affected Intel Pentium, Celeron, Atom, and Pentium Silver processors within your environment
• Review and apply the latest BIOS/firmware updates from your system or motherboard manufacturer that incorporate Intel's security fixes
• Restrict local administrative access to only essential personnel to minimize the attack surface
• Enable Secure Boot and maintain firmware integrity monitoring to detect unauthorized modifications

Patch Information

Intel has released security guidance through Intel Security Advisory SA-00813 addressing this vulnerability. Organizations should contact their system OEM or motherboard manufacturer to obtain the appropriate BIOS firmware update that incorporates Intel's security fixes. NetApp has also published Advisory NTAP-20230824-0001 for affected NetApp products using these Intel processors.

Firmware updates must be obtained from the specific system vendor (Dell, HP, Lenovo, etc.) or motherboard manufacturer, as BIOS updates are customized for each hardware platform.

Workarounds

• Implement strict access controls to limit local administrative privileges and reduce the pool of potential attackers who could exploit this vulnerability
• Deploy defense-in-depth measures including endpoint protection that monitors for privilege escalation and anomalous system behavior
• Utilize Secure Boot and measured boot technologies to ensure firmware integrity and detect tampering
• Consider hardware isolation for systems processing highly sensitive data until firmware patches can be applied

# Example: Verify current BIOS version on Linux systems
sudo dmidecode -s bios-version
sudo dmidecode -s bios-release-date

# Check for Intel processor identification
cat /proc/cpuinfo | grep -E "model name|vendor_id"

# Verify Secure Boot status
mokutil --sb-state