A straightforward tool for exploiting SMTP Smuggling vulnerabilities (https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/).
$ ./SmuggleTP.py -h
usage: SmuggleTP.py [-h] --smtp_server SMTP_SERVER --smtp_port SMTP_PORT [--smtp_username SMTP_USERNAME] [--smtp_password SMTP_PASSWORD] --sender_email SENDER_EMAIL --receiver_email
RECEIVER_EMAIL --spoofed_email SPOOFED_EMAIL [--enable_debug]
options:
-h, --help show this help message and exit
--smtp_server SMTP_SERVER
SMTP server hostname
--smtp_port SMTP_PORT
SMTP server port
--smtp_username SMTP_USERNAME
SMTP username
--smtp_password SMTP_PASSWORD
SMTP password
--sender_email SENDER_EMAIL
Sender email address
--receiver_email RECEIVER_EMAIL
Receiver email address
--spoofed_email SPOOFED_EMAIL
Spoofed email address
--enable_debug Enable SMTP debug messages
If you have received an email from SPOOFED_EMAIL to RECEIVER_EMAIL, it's likely that the exploit worked.