Zero Day Security is an independent penetration testing practice. Every engagement is led by a CREST CRT and OSCP certified tester, so you work directly with the expert doing the testing, not a junior running a scanner.
In security there is no room for good enough. A single vulnerability can be the way in for a breach, so every engagement aims to find every exploitable weakness and help you fix it before an attacker finds it.
Automated discovery maps your attack surface, then a CREST CRT and OSCP certified tester manually tests and validates every finding, including business logic flaws that no scanner can catch.
Lean operations and efficient tooling mean results in 1-2 weeks and fixed prices well below traditional firms, without cutting corners on quality. Every engagement includes a free retest.
CREST Registered Penetration Tester and Practitioner Security Analyst: practical certifications that must be renewed, recognised by regulators and procurement teams in the US, UK and worldwide.
OffSec certifications in hands-on penetration testing, web application attacks and wireless security, each earned by passing a timed practical exam against live targets.
Hack The Box's specialist certification in attacking AI and LLM applications, covering prompt injection, AI agent and tool abuse, and data leakage through RAG pipelines.
Anything else you would like to know? Email info@zerodaysecurity.net.
A CREST CRT and OSCP certified tester performs every engagement personally, from scoping through testing, reporting and the retest. There is no handoff to a junior tester or an automated scanner, and you can talk directly to the person doing the work.
Zero Day Security is based in Colorado and tests remotely for organizations across the United States. On-site work, such as wireless testing, can be arranged when needed.
No. The CREST CRT and CPSA certifications are held by the tester who performs your engagement, which is what most PCI DSS, HIPAA and SOC 2 programs need. If your contract specifically requires a CREST-accredited company, tell us during scoping and we will be upfront about it.
The tester behind Zero Day Security has hands-on experience testing SaaS platforms and APIs, healthcare and health tech systems that handle ePHI, fintech and payment environments in PCI DSS scope, and eCommerce sites. Zero Day Security offers that same testing directly to small and mid-sized businesses.
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CREST CRT, OSCP, OSWA, OSWP, HTB COAE certified