In the world of cybersecurity, a vulnerability is a term to describe a weakness that opens up an opportunity to be exploited by cybercriminals to gain unauthorised access to a computer system. After exploiting a vulnerability, a cyberattack can install malware run malicious code as well as steal sensitive data.

Vulnerabilities are open to exploitation by a variety of ways including SQL injection, buffer overflows, cross-site scripting (XSS) and open-source exploit kits that look for known vulnerabilities and security weaknesses in web applications.

Many vulnerabilities impact popular software, placing the many customers using the software at a heightened risk of a data breach, or supply chain attack. Such zero-day exploits are registered by MITRE as a Common Vulnerability Exposure (CVE).