testssl

name	testssl
description	Auth/lab ref: testssl.sh: broad TLS/SSL testing script checking protocol support, cipher suites, vulnerabilities (BEAST, POODLE, Heartbleed, ROBOT, DROWN, etc.), and certificate issues.
license	GPL-2.0
compatibility	Linux / macOS / Windows (WSL/Cygwin); Bash 3.2+, OpenSSL or LibreSSL.
metadata	{"author":"AeonDave","version":"1.0"}

testssl.sh

TLS/SSL testing script — protocols, ciphers, vulnerabilities, certificates.

Quick Start

# Full scan (all checks)
testssl.sh https://target.com

# Specific port
testssl.sh target.com:8443

# STARTTLS (mail server)
testssl.sh --starttls smtp mail.target.com:25

Core Flags

Flag	Purpose
-p	Check protocols (SSLv2/3, TLS 1.0-1.3)
-s	List cipher suites (preferred + supported)
-f	Check forward secrecy
-h	Check HSTS / HPKP
-U	Test all vulnerabilities
-E	List cipher suites per protocol
-B	Heartbleed (OpenSSL vulnerability)
--beast	BEAST attack check
--breach	BREACH check
--crime	CRIME check
--lucky13	Lucky13 timing attack
--poodle	POODLE (SSLv3)
--sweet32	Birthday attacks on 64-bit block ciphers
--logjam	Logjam (DH key exchange weakness)
--drown	DROWN attack (SSLv2 overlap)
--ticketbleed	Ticketbleed (F5 vulnerability)
--robot	ROBOT attack
--tls-fallback	TLS_FALLBACK_SCSV check
-e	List all supported ciphers
--protocols	List supported protocols only
--server-defaults	Server defaults (cert, session, etc.)
--server-preference	Server cipher preference
--client-simulation	Simulate handshake with common clients
--starttls <proto>	STARTTLS: smtp / pop3 / imap / ftp / xmpp / ldap
--mx	Test all MX records of a domain (mail servers)
--file <file>	Batch mode — one target per line
--mode parallel	Run batch in parallel (use with --file)
--outprefix <str>	Prefix for all output files in batch mode
--append	Append to existing output file
--ip <ip>	Force specific IP for SNI hosts
--proxy <host:port>	SOCKS5/HTTP proxy
--sneaky	Sneaky mode (minimal headers)
--ids-friendly	Avoid IDS trigger patterns
-t <n>	Timeout per connection
--connect-timeout <n>	Connection timeout
--openssl <path>	Specify OpenSSL binary to use
-oJ <file>	JSON output
-oC <file>	CSV output
-oH <file>	HTML output
-oA <file>	All output formats (adds extensions)
--color <0-3>	Color output level
--quiet	Minimal output
--warnings batch	Batch mode (no interactive prompts)
--parallel	Parallel testing (faster, less reliable)
--nodns <min>	Skip DNS reverse lookups

Vulnerability Checks (-U runs all)

Flag	Vulnerability	Impact
--heartbleed	Heartbleed (CVE-2014-0160)	Memory leak → private key
--ccs	CCS Injection (CVE-2014-0224)	MITM
--ticketbleed	Ticketbleed (CVE-2016-9244)	Memory leak
--robot	ROBOT (RSA PKCS#1 oracle)	RSA key recovery
--breach	BREACH	HTTP compression info leak
--crime	CRIME	TLS compression info leak
--beast	BEAST	CBC mode attack (TLS 1.0)
--poodle	POODLE	SSLv3 CBC attack
--sweet32	Sweet32	3DES birthday attack
--logjam	Logjam	DH 512/1024-bit export weakness
--drown	DROWN	SSLv2 cross-protocol attack
--lucky13	Lucky13	CBC timing attack
--tls-fallback	Downgrade fallback	Missing SCSV
--freak	FREAK	Export RSA key exchange
--rc4	RC4 biases	Statistical attacks

# Individual vuln flags (short form):
# -H heartbleed  -I CCS  -T ticketbleed  --BB ROBOT  -R renegotiation
# -C CRIME  -B BREACH  -O POODLE  -Z fallback  -W SWEET32
# -F FREAK  -D DROWN  -J LOGJAM  -A BEAST  -L LUCKY13  -4 RC4

Protocol & Cipher Assessment

# Protocol support check
testssl.sh -p target.com
# Look for: SSLv2 (critical), SSLv3 (critical), TLS 1.0/1.1 (warn)

# Cipher suites
testssl.sh -s target.com
# Look for: NULL, EXPORT, DES, RC4, 3DES (all bad)
# Want: AESGCM, CHACHA20, ECDHE (good)

# Check for forward secrecy (PFS)
testssl.sh -f target.com
# ECDHE/DHE = PFS available; RSA key exchange = no PFS

# Full cipher enumeration
testssl.sh -E target.com

Common Workflows

# Full assessment with all checks
testssl.sh -U -p -s -h -f --server-defaults target.com

# Quick vuln check only (fast)
testssl.sh -U --quiet target.com

# STARTTLS mail server
testssl.sh --starttls smtp mail.target.com:587
testssl.sh --starttls imap mail.target.com:143

# JSON output for reporting
testssl.sh --jsonfile report.json -U target.com

# HTML report
testssl.sh -oH report.html -U -p -s target.com

# All formats at once
testssl.sh -oA report -U -p -s -f target.com
# Creates: report.json, report.csv, report.html

# Client simulation (browser compatibility)
testssl.sh --client-simulation target.com

# Batch scan with built-in file mode (one target per line):
# targets.txt can contain: host:port, -t smtp host:587, etc.
testssl.sh --file targets.txt --warnings batch -U --quiet

# Parallel batch scan (built-in):
testssl.sh --file targets.txt --mode parallel --warnings batch \
    -oA pentest-$(date +%Y%m%d)  # creates .json .csv .html per target

# Test all mail servers (MX records) for domain:
testssl.sh --mx example.com

# Stealth / IDS-evasion mode:
testssl.sh --sneaky --ids-friendly --nodns min -U target.com

Key Findings for Reports

Finding	Severity	Recommendation
SSLv2 enabled	Critical	Disable immediately
SSLv3 enabled	Critical	Disable (POODLE)
TLS 1.0 enabled	Medium/High	Disable if possible
Heartbleed	Critical	Patch OpenSSL
ROBOT	High	Disable RSA key exchange
NULL ciphers	Critical	Remove
EXPORT ciphers	Critical	Remove
RC4 ciphers	High	Remove
3DES (Sweet32)	Medium	Remove
DH < 2048-bit	Medium	Use 2048+ bit DH
Self-signed cert	Medium	Replace with trusted CA
Expired cert	High	Renew certificate
No HSTS	Low/Medium	Add Strict-Transport-Security
No PFS	Medium	Enable ECDHE ciphers
SHA1 certificate	Medium	Replace with SHA256+

Output Parsing

# Extract findings from JSON
cat report.json | jq '.[] | select(.severity != "OK" and .severity != "INFO") | {id: .id, severity: .severity, finding: .finding}'

# Count by severity
cat report.json | jq '[.[] | .severity] | group_by(.) | map({severity: .[0], count: length})'

# Extract certificate info
cat report.json | jq '.[] | select(.id | startswith("cert")) | {id: .id, finding: .finding}'

# Find critical/high findings only
cat report.json | jq '.[] | select(.severity == "CRITICAL" or .severity == "HIGH") | {id, finding}'

Resources

File	When to load
references/tls-hardening.md	TLS configuration best practices, cipher suite recommendations, HSTS setup