AppCheck is a UK-based software security vendor that provides an automated security scanning platform for discovering vulnerabilities in websites, applications, network infrastructure, and cloud environments. The company originated in 2003 as an internal penetration testing tool and began commercial operations in 2014. The platform uses proprietary scanning technology developed and maintained by penetration testing experts, designed to bridge the gap between manual and automated testing by emulating the methodologies of manual penetration testers. The company specializes in testing complex websites and applications, using a first principles methodology to detect difficult-to-find security flaws beyond those with known signatures. The platform enables users to run unlimited and continuous scans with unlimited user licenses, allowing multiple departments to test various environments including live, UAT, and SDLC. Discovered vulnerabilities can be tracked and analyzed through an integrated vulnerability management platform. In 2019, AppCheck launched a scanning engine capable of testing single page applications built with JavaScript. In 2021, the company became authorized as a CVE Numbering Authority (CNA) by the Common Vulnerabilities and Exposures Program. AppCheck serves a range of clients from SMEs and educational institutions to public sector and enterprise organizations through a global partner program and direct sales team. The company offers multiple scalable license models and tailored support services based on client requirements and technical expertise.