Secure Boot Assessment
Evaluation of boot chain integrity, cryptographic signing, key storage, and attestation mechanisms on ARM and x86 embedded platforms.
Secure Boot Assessment
Secure boot is the cryptographic chain of trust that ensures a device only executes authenticated firmware and software from power-on through to the operating system. When implemented correctly, it prevents persistent malware implants, unauthorised firmware modification, and bootkit attacks. When implemented incorrectly, attackers can bypass it entirely — rendering all subsequent security controls irrelevant.
Intelliroot's Secure Boot Assessment evaluates the complete boot chain — from ROM bootloader through UEFI or U-Boot, to the operating system kernel — testing the cryptographic integrity, key management practices, rollback protection, and bypass resistance of the entire chain of trust.
Boot Security Is the Root of All Device Trust
Bootkits Survive OS Reinstalls
Malware that persists below the OS level — in the bootloader, UEFI firmware, or option ROMs — survives operating system reinstalls, disk wipes, and factory resets. Detecting and removing such implants requires out-of-band forensic analysis and is extremely difficult for most organisations.
Rollback Attacks Enable Known Exploits
Without anti-rollback protection, attackers who compromise firmware signing keys can downgrade devices to older, vulnerable firmware versions — re-enabling previously patched vulnerabilities. Anti-rollback validation is a critical but often overlooked component of secure boot.
Key Management Is Frequently Flawed
Signing keys stored in software, shared across device families, or generated with insufficient entropy are common findings. A single compromised signing key can be used to sign malicious firmware that passes secure boot validation on millions of deployed devices.
UEFI Vulnerabilities Are Rarely Patched
UEFI firmware vulnerabilities frequently persist unpatched for years because OEM firmware update processes are complex and rarely automated. Several nation-state-linked threat actors (LoJax, MosaicRegressor, CosmicStrand) specifically target UEFI as a persistence mechanism.
What We Assess
Boot Chain Analysis
ROM bootloader, secondary bootloader (U-Boot, GRUB), UEFI/BIOS, kernel image verification. Complete chain-of-trust walkthrough from power-on.
Cryptographic Implementation
Signature algorithm selection, key sizes, certificate chain validation, and cryptographic library version assessment. Identification of weak or obsolete algorithms.
Key Storage & Management
TPM integration, hardware security module usage, key derivation practices, and key revocation mechanisms. Assessment of key storage security in hardware vs. software.
Bypass Simulation
Practical bypass testing including fault injection against boot validation, debug interface abuse, and physical memory attacks to validate bypass resistance.
Our Approach
- 01
Architecture Review
Review secure boot architecture documentation, design specifications, and threat models. Identify the boot chain components and expected security properties.
- 02
Bootloader & Firmware Analysis
Extract and analyse each stage of the boot chain. Verify signature verification logic, identify bypass conditions, and assess cryptographic implementation quality.
- 03
Key Management Assessment
Assess signing key generation, storage, rotation, and revocation processes. Evaluate TPM/HSM integration and identify key exposure risks.
- 04
Anti-Rollback Validation
Test rollback protection mechanisms by attempting to boot downgraded firmware images. Validate monotonic counter implementations and fuse-based version controls.
- 05
Bypass Testing
Practical bypass attempts using fault injection, debug interface manipulation, and physical attacks. Document successful bypass techniques and required attack complexity.
Deliverables
Secure Boot Assessment Report
Technical report covering all boot chain components, identified weaknesses, bypass findings, and recommendations for each stage of the chain of trust.
Key Management Review
Assessment of signing key practices with specific recommendations for key generation, storage, rotation, and revocation process improvements.
Boot Chain Architecture Diagram
Annotated diagram of the assessed boot chain identifying each component, its role in the chain of trust, and identified security gaps.
Hardening Recommendations
Prioritised secure boot hardening recommendations covering cryptographic upgrades, key management improvements, and anti-rollback implementation guidance.
Request a Security Assessment
Tell us about your environment and security objectives. We'll design a bespoke assessment and deliver a detailed proposal within 48 hours.