In cybersecurity, SMTP Cracker is a controversial tool designed to test and exploit Simple Mail Transfer Protocol (SMTP) servers. While marketed as a security testing utility, its capabilities raise significant ethical and legal concerns.
Download Server 1 Download Server 2 Download Server 3 
What is SMTP Cracker?
SMTP Cracker 2.1 is a Windows-based penetration testing tool that enables:
- Brute-force attacks against SMTP servers.
- Authentication testing.
- Open relay detection.
- Email address verification.
Technical Features
1. Authentication Testing
- Supports LOGIN, PLAIN, CRAM-MD5 auth methods.
- Tests 50+ combinations/second (performance varies).
- Automatic protocol detection.
2. Server Analysis
- Open relay detection.
- User enumeration.
- Banner grabbing.
- TLS/SSL support checking.
3. Reporting
- Success/failure logs.
- Session transcripts.
- Vulnerability summaries.
