testssl.sh
testssl.sh checks a server's TLS/SSL ciphers, protocols and known cryptographic flaws from the command line.
Legal & ethical use. Use this tool only on systems, networks and data that you own or have explicit written permission to test. Unauthorised access or scanning can break computer-misuse laws (for example Pakistan's Prevention of Electronic Crimes Act, 2016, and equivalents elsewhere). Practise in your own lab or in authorised environments such as CTFs.
What it is used for
- Audit the TLS setup of your own website
- Verify a hardening change
Key features
- Protocol and cipher checks
- Vulnerability checks
- Single shell script
Installation
git clone https://github.com/testssl/testssl.sh.git
Beginner usage guide
Run it against a host you own and fix anything flagged in red.
Example commands
Run these only against your own lab or authorised targets. Placeholder addresses such as 192.0.2.x are documentation ranges.
Test a host
./testssl.sh example.comRuns the default set of TLS checks against the host.
References
Source verification
Last reviewed: 2026-10-27
Links checked over HTTP: 2026-10-27 07:51 UTC — official: 200, docs: 200, repo: 200
Commands were written from the official documentation and have not been executed on this site; test them in your lab.