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Mailsploit Emailing Spoofing

Mailsploit is a new way to easily spoof email addresses when sending emails. It allows the attacker to display any email address as the from address to the email recipient by modifying the header of the email.
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Summary

Mailsploit is a new way to easily spoof email addresses when sending emails. It allows the attacker to display any email address as the from address to the email recipient by modifying the header of the email.

Threat details

The header of the email is modified in such a way that the mail clients ignore the real from address and show the spoofed email address. The "Reply To" is also modified in the headers to ensure the glitch isn't noticed. Using this method circumvents spoofing protection mechanisms such as DMARC (DKIM/SPF) and spam filters.

In addition to the spoofing vulnerability, some of the tested applications also proved to be vulnerable to XSS and code injection attacks.


Remediation steps

Type Step
Ensure that all email clients are patched and up-to-date

Last edited: 17 February 2020 11:34 am