🔬 Advanced Firmware Auditing

BIOS / UEFI Security Audit Methodology

Comprehensive firmware integrity verification, SPI flash forensics, supply chain risk assessment, and low-level platform security analysis for enterprise and embedded systems.

Firmware Images Analyzed

250+ real-world samples

Vulnerabilities Identified

1,200+

OEM Vendors Assessed

25+

What Is a BIOS/UEFI Security Audit?

A systematic examination of platform firmware to identify vulnerabilities, persistence mechanisms, integrity violations, and supply chain risks that traditional security controls cannot detect.

🔍 Firmware Integrity

Cryptographic hash verification against known good baselines; detection of unauthorized modifications, backdoors, and implanted modules.

⚙️ Configuration Security

Review of Secure Boot settings, UEFI variables, boot order, DMA protection, and administrative password policies.

🛡️ Supply Chain Risk

Assessment of firmware provenance, vendor signing practices, update mechanisms, and hardware root-of-trust implementations.

UEFI Boot Chain & Attack Surface

SEC PEI DXE ⚠️ BDS TSL ⚠️ RT Critical attack surface Bootkit injection window

DXE and TSL phases represent primary firmware attack surface

5‑Phase Audit Methodology

Our proprietary framework combines static analysis, dynamic testing, and forensic examination.

📡 Phase 1 – Reconnaissance & Baseline Capture

Extract current firmware image via SPI flash programmer or in‑system tools. Document vendor, version, build date, and UEFI capabilities. Establish integrity baseline using cryptographic hashes (SHA‑256, SHA‑3).

🔧 Phase 2 – Static Firmware Analysis

Parse firmware structure using UEFITool, CHIPSEC, and binwalk. Identify PEI/DXE/SMM modules. Detect anomalies: unknown modules, code caves, modified sections, unexpected strings.

💾 Phase 3 – SPI Flash Forensics

Physical SPI flash read via dedicated programmer (e.g., Dediprog, Flashcat). Compare against vendor baseline. Identify HPA/DCO regions, malicious implants, and configuration drift.

⚡ Phase 4 – Runtime & Boot‑Time Validation

Execute controlled boot sequence monitoring. Verify Secure Boot enforcement, measure PCR values, detect WPBT abuse, validate runtime services integrity.

📋 Phase 5 – Risk Assessment & Remediation

Prioritize findings based on CVSS scoring, exploitability, and business impact. Deliver actionable remediation roadmap including vendor patching, configuration hardening, and supply chain recommendations.

SPI Flash Memory Layout

0x00000000 – 0x000FFFFF Descriptor Region (Flash Map, Master Access)
0x00100000 – 0x01FFFFFF BIOS/ME Region (UEFI firmware, DxE drivers) ⚠️
0x02000000 – 0x020FFFFF GbE Region (MAC addresses, config)
0x02100000 – 0x03FFFFFF PDR / Reserved

Malicious implants typically reside in BIOS Region (0x00100000+)

Audit Toolchain

Industry‑standard and proprietary tools used during assessment.

🔧 CHIPSEC

Platform security assessment framework by Intel. SPI flash analysis, UEFI variable inspection.

📦 UEFITool

Firmware image parsing, module extraction, section‑level analysis.

🔍 Binwalk

Entropy analysis, file carving, embedded payload detection.

🐉 Ghidra

Reverse engineering of DxE drivers, PEI modules, UEFI binaries.

💾 Dediprog SF100/600

Hardware SPI flash reader for physical extraction.

📊 Custom Scripts

Python automation for hash validation, module fingerprinting.

Common Findings

  • 🔴 Critical: Insecure Secure Boot configuration (disabled / custom mode / default PK)
  • 🔴 Critical: Outdated DBX revocation list → vulnerable to BlackLotus‑style downgrade attacks
  • 🟠 High: Unexpected/malicious DxE modules in firmware image
  • 🟠 High: WPBT‑capable firmware without WDAC enforcement
  • 🟡 Medium: Unprotected SPI flash (no BIOS lock / PRx)
  • 🟡 Medium: Debug interfaces exposed (JTAG, UART) in production devices

Why GGsec for Firmware Auditing?

🎯 Specialized Expertise

Dedicated firmware security practice – not general pentesting. Our analysts reverse engineer UEFI implants daily.

🔬 Hardware Lab

In‑house SPI programmers, logic analyzers, and rework station for physical firmware extraction and analysis.

📄 Actionable Reports

Executive summary + technical annex with step‑by‑step reproduction, code snippets, and prioritized fixes.

Ready to Secure Your Firmware?

Schedule a confidential discovery call to discuss your audit scope.

Request BIOS/UEFI Audit →