# testssl.sh | Dirk Wetter | Knowledge Base | Instagit

GitHub Stars: 0

Repository: https://github.com/drwetter/testssl.sh

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## Articles

### [How to Test TLS Renegotiation and Session Resumption with testssl.sh](/drwetter/testssl.sh/testssl-sh-tls-renegotiation-session-resumption)

Easily test TLS renegotiation and session resumption with testssl.sh. Use the -R flag for RFC 5746 renegotiation and -S for session IDs tickets & TLS 1.3 0-RTT.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Customize testssl.sh Behavior Using Environment Variables: A Complete Guide](/drwetter/testssl.sh/customize-testssl-sh-environment-variables)

Learn how to customize testssl.sh behavior using environment variables to set default options. Configure the SSL/TLS scanner permanently without altering command lines. Get the complete guide.

- Tags: how-to-guide
- Published: 2026-03-01

### [Understanding the testssl.sh Rating System: How Grades Are Calculated and What They Mean](/drwetter/testssl.sh/understand-testssl-sh-rating-system)

Understand the testssl.sh rating system. Learn how protocol support, key exchange, and cipher strength determine grades from A to F for your SSL server.

- Tags: deep-dive
- Published: 2026-03-01

### [How to Test for TLS Compression Vulnerabilities (CRIME & BREACH) with testssl.sh](/drwetter/testssl.sh/testssl-sh-test-tls-compression-crime-breach)

Easily test for TLS compression vulnerabilities like CRIME and BREACH using the testssl.sh tool. Learn how to secure your servers by identifying and mitigating these risks.

- Tags: how-to-guide
- Published: 2026-03-01

### [Performance Tuning testssl.sh for Large-Scale Scans: A Technical Guide](/drwetter/testssl.sh/performance-tuning-testssl-sh-large-scans)

Boost testssl.sh performance for large scans. Learn to tune parallel mode, MAX_PARALLEL, native SSL, and disable checks for faster results. Maximize efficiency.

- Tags: performance
- Published: 2026-03-01

### [testssl.sh vs SSL Labs: How the Open-Source TLS Scanner Compares to Online Tools](/drwetter/testssl.sh/testssl-sh-vs-ssl-labs-comparison)

Compare testssl.sh and SSL Labs for TLS testing. Discover how the open-source scanner offers local privacy, custom ports, and CI/CD integration.

- Tags: comparison
- Published: 2026-03-01

### [How to Integrate testssl.sh with Nagios and Icinga for Automated TLS Monitoring](/drwetter/testssl.sh/integrate-testssl-sh-with-nagios-icinga)

Integrate testssl.sh with Nagios and Icinga for automated TLS monitoring. Leverage plugins to translate exit codes and output into service states for proactive SSL health and vulnerability alerts.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Identify Weak Ciphers and Deprecated Protocols Using testssl.sh](/drwetter/testssl.sh/testssl-sh-find-weak-ciphers-deprecated-protocols)

Easily identify weak ciphers and deprecated protocols with testssl.sh. Discover vulnerabilities and secure your servers with this essential security tool. Learn how now.

- Tags: how-to-guide
- Published: 2026-03-01

### [Common testssl.sh Command-Line Options and Flags: A Complete Guide](/drwetter/testssl.sh/testssl-sh-command-line-options-flags)

Master testssl.sh command-line options and flags. This guide covers essential switches to efficiently scan TLS/SSL configurations and identify vulnerabilities. Optimize your security checks today.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Test OCSP Stapling and Certificate Revocation Status with testssl.sh](/drwetter/testssl.sh/testssl-sh-ocsp-stapling-revocation)

Easily test OCSP stapling and certificate revocation status with testssl.sh. This powerful tool checks external OCSP responders and CRLs for accurate validation directly from TLS handshakes.

- Tags: how-to-guide
- Published: 2026-03-01

### [How testssl.sh Tests HTTP Security Headers: Deep Dive into HSTS, HPKP, and Cookie Flag Detection](/drwetter/testssl.sh/testssl-sh-http-security-headers-testing)

Discover how testssl.sh analyzes HTTP security headers like HSTS, HPKP, and cookie flags. Learn about its specialized parsing functions and validation against minimum thresholds.

- Tags: deep-dive
- Published: 2026-03-01

### [How to Run testssl.sh Within Docker Containers: Complete Guide](/drwetter/testssl.sh/run-testssl-sh-in-docker)

Learn to run testssl.sh in Docker containers. Use the official image and pass scanner arguments directly with host directory bind mounts for output. Get started now.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Debug Connection Issues When Running testssl.sh](/drwetter/testssl.sh/debug-testssl-sh-connection-issues)

Troubleshoot testssl.sh connection problems with the --debug flag for file inspection, adjusting MAX_OSSL_FAIL and MAX_SOCKET_FAIL to manage transient errors and get clearer output.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Simulate Different Client Environments for TLS Compatibility Testing with testssl.sh](/drwetter/testssl.sh/testssl-sh-client-simulation-compatibility)

Simulate diverse client environments for TLS testing with testssl.sh. Mimic browser OS and TLS client behavior to ensure compatibility across platforms.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Use testssl.sh for Certificate Chain Validation and CA Trust Checking](/drwetter/testssl.sh/testssl-sh-certificate-chain-validation)

Learn to validate certificate chains and check CA trust with testssl.sh. This tool verifies server certificates against major trust stores using OpenSSL and supports custom CAs.

- Tags: how-to-guide
- Published: 2026-03-01

### [How testssl.sh Tests for Forward Secrecy (FS): Configuration and Implementation](/drwetter/testssl.sh/testssl-sh-forward-secrecy-testing)

Discover how testssl.sh tests Forward Secrecy by filtering cipher suites and attempting handshakes. Learn its configuration options for comprehensive TLS security checks.

- Tags: deep-dive
- Published: 2026-03-01

### [Understanding testssl.sh Exit Codes and Error Handling](/drwetter/testssl.sh/testssl-sh-exit-codes-error-handling)

Master testssl.sh exit codes! Understand numeric codes from 0 to 255 to effectively handle environmental failures connectivity issues and scan results. Improve your scripts now.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Perform Mass Scanning of Multiple Hosts Using testssl.sh: Complete Guide](/drwetter/testssl.sh/testssl-sh-mass-scanning-multiple-hosts)

Learn how to perform mass scanning of multiple hosts with testssl.sh using the --file and --mode parallel options. Scan your infrastructure efficiently and concurrently.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Test TLS 1.3 Support and Available Cipher Suites with testssl.sh](/drwetter/testssl.sh/testssl-sh-tls-1-3-cipher-suites)

Easily test TLS 1.3 support and available cipher suites with testssl.sh. Discover how this powerful tool verifies your server's security configuration and identifies supported protocols.

- Tags: how-to-guide
- Published: 2026-03-01

### [How to Configure testssl.sh to Use a Specific or Custom OpenSSL Binary](/drwetter/testssl.sh/configure-testssl-sh-custom-openssl)

Configure testssl.sh to use a specific OpenSSL binary. Learn to set the OPENSSL environment variable or use the --openssl command-line flag for custom OpenSSL installations. Ensure accurate SSL/TLS testing.

- Tags: how-to-guide
- Published: 2026-03-01

### [Can testssl.sh Test Non-HTTP Services with STARTTLS? Protocol Support Guide](/drwetter/testssl.sh/testssl-sh-starttls-non-http-services)

Discover how testssl.sh tests non-HTTP services like SMTP FTP and XMPP with STARTTLS. Learn to perform complete TLS handshakes using the t flag for comprehensive security checks.

- Tags: deep-dive
- Published: 2026-03-01

### [How to Integrate testssl.sh into CI/CD Pipelines for Automated TLS/SSL Testing](/drwetter/testssl.sh/integrate-testssl-sh-into-ci-cd)

Automate TLS SSL testing by integrating testssl.sh into your CI CD pipelines. Learn how to add simple shell steps for continuous security checks.

- Tags: how-to-guide
- Published: 2026-02-28

### [testssl.sh Output Formats: JSON, CSV, and HTML Options Explained](/drwetter/testssl.sh/testssl-sh-output-formats-json-csv-html)

Master testssl.sh output formats JSON CSV and HTML. Learn how to use command line flags to generate machine readable files and easily analyze your SSL/TLS scan results.

- Tags: how-to-guide
- Published: 2026-02-28

### [How to Test for TLS Vulnerabilities (Heartbleed, POODLE, BEAST) Using testssl.sh](/drwetter/testssl.sh/how-to-test-tls-vulnerabilities-with-testssl-sh)

Test for TLS vulnerabilities like Heartbleed POODLE and BEAST using testssl.sh. Discover and fix security flaws in your TLS protocol stack with targeted vulnerability checks.

- Tags: how-to-guide
- Published: 2026-02-28