11 FREE SSL/TLS Troubleshooting Tools for Webmaster

You often need to debug SSL/TLS related issues while working as a web engineer, webmaster, or system administrator.

There are plenty of online tools for SSL certificate, Testing SSL/TLS vulnerabilities, but when it comes to testing intranet-based URL, VIP, IP, then they won’t be helpful.

To troubleshoot intranet resources, you need a standalone software/tools which you can install in your network and perform a necessary test.

There could be various scenarios, like:

Having issues during SSL certificate implementation with webserver
Want to ensure latest/particular cipher, protocol is being used
Post-implementation, wish to verify the configuration
Security risk found in a penetration test result

The following tools will be handy to troubleshoot such issues.

DeepViolet

DeepViolet is a java based SSL/TLS scanning tool available in binary, or you can compile with source code.

If you are looking for an alternative of SSL Labs to be used on an internal network, then DeepViolet would be a good pick. It scans for the following.

Weak cipher exposed
Weak signing algorithm
Certification revocation status
Certificate expiry status
Visualize trust-chain, a self-signed root

SSL Diagnos

Quickly evaluate the SSL strength of your web site. SSL Diagnos extract SSL protocol, cipher suites, heartbleed, BEAST.

Not just HTTPS, but you can test SSL strength for SMTP, SIP, POP3, and FTPS.

SSLyze

SSLyze is a Python library and command-line tool which connects to SSL endpoint and performs a scan to identify any SSL/TLS miss-configuration.

Scan through SSLyze is fast as a test is distributed through multiple processes. If you are a developer or you would like to integrate with your existing application, then you have an option to write the result in XML or JSON format.

SSLyze is also available in Kali Linux. If you are new to Kali then check out how to install Kali Linux on VMWare Fusion.

OpenSSL

Don’t underestimate OpenSSL, one of the powerful standalone tools available for Windows or Linux to perform various SSL related tasks like verification, CSR generation, certification conversion, etc.

SSL Labs Scan

Love Qualys SSL Labs? You are not alone; I love it too.

If you are looking for a command-line tool for SSL Labs for automated or bulk testing, then SSL Labs Scan would be useful.

SSL Scan

SSL Scan is compatible with Windows, Linux, and MAC. SSL Scan quickly helps to identify the following metrics.

Highlight SSLv2/SSLv3/CBC/3DES/RC4/ ciphers
Report weak (<40bit), null/anonymous ciphers
Verify TLS compression, heartbleed vulnerability
and much more…

If you are working on cipher related issues, then an SSL scan would be a helpful tool to fast-track the troubleshooting.

Geekflare TLS Scanner API

Another nifty solution for webmasters can be the Geekflare TLS Scanner API.

This is a robust method to check the TLS protocol, CN, SAN, and other certificate details in a split second. And you can try this risk-free with a no-cost subscription for up to 3000 requests per month.

However, the base premium tier adds a greater request rate and 10K API calls for just $5 a month.

TestSSL

As the name indicates, TestSSL is a command-line tool compatible with Linux or OS. It tests all the essential metrics and gives status, whether good or bad.

Ex:

Testing protocols via sockets except SPDY+HTTP2

SSLv2 not offered (OK)
SSLv3 not offered (OK)
TLS 1 offered
TLS 1.1 offered
TLS 1.2 offered (OK)
SPDY/NPN h2, spdy/3.1, http/1.1 (advertised)
HTTP2/ALPN h2, spdy/3.1, http/1.1 (offered)

Testing ~standard cipher categories

NULL ciphers (no encryption) not offered (OK)
Anonymous NULL Ciphers (no authentication) not offered (OK)
Export ciphers (w/o ADH+NULL) not offered (OK)
LOW: 64 Bit + DES encryption (w/o export) not offered (OK)
Weak 128 Bit ciphers (SEED, IDEA, RC[2,4]) not offered (OK)
Triple DES Ciphers (Medium) not offered (OK)
High encryption (AES+Camellia, no AEAD) offered (OK)
Strong encryption (AEAD ciphers) offered (OK)

Testing server preferences

Has server cipher order? yes (OK)
Negotiated protocol TLSv1.2
Negotiated cipher ECDHE-ECDSA-CHACHA20-POLY1305-OLD, 256 bit ECDH (P-256)
Cipher order
TLSv1: ECDHE-RSA-AES128-SHA AES128-SHA ECDHE-RSA-AES256-SHA AES256-SHA DES-CBC3-SHA 
TLSv1.1: ECDHE-RSA-AES128-SHA AES128-SHA ECDHE-RSA-AES256-SHA AES256-SHA 
TLSv1.2: ECDHE-ECDSA-CHACHA20-POLY1305-OLD ECDHE-ECDSA-CHACHA20-POLY1305 ECDHE-ECDSA-AES128-GCM-SHA256
ECDHE-ECDSA-AES128-SHA ECDHE-ECDSA-AES128-SHA256 ECDHE-ECDSA-AES256-GCM-SHA384
ECDHE-ECDSA-AES256-SHA ECDHE-ECDSA-AES256-SHA384 ECDHE-RSA-CHACHA20-POLY1305-OLD
ECDHE-RSA-CHACHA20-POLY1305 ECDHE-RSA-AES128-GCM-SHA256 ECDHE-RSA-AES128-SHA
ECDHE-RSA-AES128-SHA256 AES128-GCM-SHA256 AES128-SHA AES128-SHA256
ECDHE-RSA-AES256-GCM-SHA384 ECDHE-RSA-AES256-SHA ECDHE-RSA-AES256-SHA384 AES256-GCM-SHA384
AES256-SHA AES256-SHA256

Testing vulnerabilities

Heartbleed (CVE-2014-0160) not vulnerable (OK), no heartbeat extension
CCS (CVE-2014-0224) not vulnerable (OK)
Ticketbleed (CVE-2016-9244), experiment. not vulnerable (OK)
Secure Renegotiation (CVE-2009-3555) not vulnerable (OK)
Secure Client-Initiated Renegotiation not vulnerable (OK)
CRIME, TLS (CVE-2012-4929) not vulnerable (OK)
BREACH (CVE-2013-3587) potentially NOT ok, uses gzip HTTP compression. - only supplied "/" tested
Can be ignored for static pages or if no secrets in the page
POODLE, SSL (CVE-2014-3566) not vulnerable (OK)
TLS_FALLBACK_SCSV (RFC 7507) Downgrade attack prevention supported (OK)
SWEET32 (CVE-2016-2183, CVE-2016-6329) not vulnerable (OK)
FREAK (CVE-2015-0204) not vulnerable (OK)
DROWN (CVE-2016-0800, CVE-2016-0703) not vulnerable on this host and port (OK)
make sure you don't use this certificate elsewhere with SSLv2 enabled services
https://censys.io/ipv4?q=EDF8A1A3D0FFCBE0D6EA4C44DB5F4BE1A7C2314D1458ADC925A30AA6235B9820 could help you to find out
LOGJAM (CVE-2015-4000), experimental not vulnerable (OK): no DH EXPORT ciphers, no DH key detected
BEAST (CVE-2011-3389) TLS1: ECDHE-RSA-AES128-SHA AES128-SHA ECDHE-RSA-AES256-SHA
AES256-SHA DES-CBC3-SHA 
VULNERABLE -- but also supports higher protocols (possible mitigation): TLSv1.1 TLSv1.2
LUCKY13 (CVE-2013-0169) VULNERABLE, uses cipher block chaining (CBC) ciphers
RC4 (CVE-2013-2566, CVE-2015-2808) no RC4 ciphers detected (OK)

As you can see, it covers a large number of vulnerabilities, cipher preferences, protocols, etc. TestSSL.sh is also available in a docker image.

If you need to do a remote scan using testssl.sh then you can try Geekflare TLS Scanner.

TLS Scan

You can either build TLS-Scan from source or download binary for Linux/OSX. It extracts certificate information from the server and prints the following metrics in JSON format.

Hostname verification checks
TLS compression checks
Cipher and TLS version enumeration checks
Session reuse checks

It supports TLS, SMTP, STARTTLS, and MySQL protocols. You may also integrate the resulting output in a logs analyzer like Splunk, ELK.

Cipher Scan

A quick tool to analyze what the HTTPS website supports all ciphers. Cipher Scan also has an option to show output in JSON format. It’s wrapper and internally using OpenSSL command.

SSL Audit

SSL audit is an open-source tool to verify the certificate and support the protocol, ciphers, and grade based on SSL Labs.

I hope the above, open-source tools help you to integrate the continuous scanning with your existing log analyzer and ease the troubleshooting.

Chandan Kumar
Contributor
- LinkedIn
Chandan Kumar is a founder of Geekflare. He is a technology enthusiast and entrepreneur who loves to help businesses and people around the world. Chandan has worked at BNP Paribas, Citibank, Deutsche Bank, Motorola, and HP. He’s got an in-depth understanding of business software and resources.