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🎣 Phishing & awareness

swaks

Swiss Army Knife for SMTP — test mail server config, deliverability, and SPF/DKIM/DMARC.

Beginner ⏱ 5 minutes 💸 Free GPLv2

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Why use it

swaks is the universal CLI tool for sending test emails. Validate SPF/DKIM/DMARC alignment, test mail server delivery from any source IP, and craft realistic phishing test messages without a full SMTP stack.

What you get

  • SMTP test sending with full header control
  • TLS testing and STARTTLS verification
  • Custom From, Reply-To, and Return-Path
  • File attachment support
  • Pipe-friendly output for scripting

System requirements

Cpuminimal
Ram50 MB
Disk5 MB
OsLinux, macOS, Windows (with Perl)
DockerYes

Installation

sudo apt install swaks. Send a test: swaks --to recipient@example.com --from test@yourdomain.com --server smtp.gmail.com:587 --auth --tls. Add --header for custom fields, --attach for files.

Suggested configuration

Use swaks to verify your DMARC alignment after any DNS change: send a test from your sending domain, check the headers in the receiving mailbox. Pair with dig on _dmarc, _dkim, _spf records.

Integration ideas

  • Use as a smoke test in CI for mail-sending services
  • Combine with GoPhish to validate deliverability before campaigns

Alternatives

  • sendemail — Older Perl tool, similar concept.
  • msmtp — More for production sending than testing.

Cyentrix verdict

In every sysadmin's muscle memory. Five minutes to install, useful forever.