Testssl.sh is an open-source command-line tool that performs comprehensive checks on a server’s TLS/SSL configuration. It tests supported protocol versions, cipher suites, certificates, and known vulnerabilities such as Heartbleed or POODLE. All you need is a Bash shell — no additional dependencies required. In an ISMS context, testssl.sh helps you verify cryptography policies and document deviations. The tool works well for both routine checks and initial assessments of new services.