All companies

US penetration testing firm founded in 2011, running 600+ engagements a year with a fully remote, US-based team. Manual, expert-led testing across web, network, cloud, mobile, wireless, OT/ICS, and AI/LLM. Gartner Sample Vendor for PTaaS.

Denver-based boutique pen testing firm with senior-only testers. Personalised engagements across penetration testing, red teaming, and vulnerability management.

US-wide pen testing firm serving major cities including Atlanta, Dallas, Denver, Houston, and Miami with security assessments.

RemoteThreat provides an offensive cyber operations platform for red teams and government mission teams.

Cloud security penetration testing specialists known for the Pacu AWS exploitation framework and deep expertise across AWS, Azure, and GCP environments.

US cybersecurity consulting, audit and testing firm founded in 2004, focused on community banks and credit unions, with external, internal, web application, wireless and PCI DSS penetration testing plus CMMC Level 1 and 2 readiness work.

The largest CPA-firm-based cybersecurity assessor in the US. Unique in holding FedRAMP 3PAO, PCI QSA, HITRUST, ISO 27001, and SOC attestation authority simultaneously.

SCYTHE provides a platform for continuous adversarial exposure validation across IT, cloud, and OT environments.

CREST-accredited information security and GRC consulting firm near Dallas. Pairs full-scope penetration testing with governance, risk, and compliance advisory and security training.

Vulnerability intelligence-driven penetration testing firm providing contextual security assessments informed by threat actor exploitation data and ransomware tracking.

Siemba provides autonomous and expert-led penetration testing for security teams.

Simbian provides AI agents that automate security operations tasks such as alert triage and threat hunting.

Adversary-focused security firm created by former DoD red team operators. Creators of BloodHound. CREST-accredited for penetration testing, red teaming, and purple team assessments.

FedRAMP-authorized crowdsourced penetration testing platform combining the vetted SRT researcher community with AI-powered Hydra technology for continuous security testing.

TestPros is an independent IT compliance firm that has been testing since 1988.

CREST-accredited California consultancy blending compliance expertise with penetration testing. First to earn ISO 17020 for MITRE ATT&CK and PTES frameworks.

Elite security research firm specializing in source code review, blockchain auditing, and building industry-standard open-source security tools.

Offensive security firm founded by former NSA operator David Kennedy, delivering CREST-accredited penetration testing, red teaming, and adversary simulation to Fortune 500 and government clients.

Global testing and certification firm, recognised by the PCI SSC for PTS POI and HSM evaluation, with labs in the UK and China.

UnderDefense provides managed detection and response, incident response, and compliance automation services.