Your search for "filtering" returned 43 results:
Sender Callout Verification
Add a new test for Sender Callout Verifications. This type of test connects back to the email sender's server and attempts to find out if the sender is valid, by starting an SMTP conversation (no email is actually sent). If the sender's email address is rejected as invalid by the sender's email server, the sender email address is considered forged and the email is blacklisted.
[Note from Vamsoft: The value and side-effects of this anti-spam technique is disputed in the industry.
For instance, simultaneous Sender Callout Verifications from thousands of servers (as a result of a major
spam breakout with forged sender email addresses) can result in a kind of Denial Of Service attack performed
against the forged sender's email servers].
3 comments
24
Recipient Validation Test Generic LDAP Support
Support non-Exchange LDAP directories (such as Novell NDS, OpenLDAP, etc.) and schemas for the Recipient Validation Test. This would allow ORF users with non-Exchange servers to take advantage of the Recipient Validation test without importing the valid recipient addresses into an SQL database or text file.
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DONE Honeypot (Spamtrap)
Blacklist the sender IP address of those writing to specific local email addresses, e.g. addresses published on
the company web site specifically as honeypot (spamtrap) addresses. This feature would be based on the assumption
that whoever sends email to the honeypot address(es) must be a wrongdoer, because the honeypot address may be
collected only by robots scanning the internet (and the web, specifically) for email addresses, which is a typical
spammer behavior.
DONE Directory Harvest Attack (DHA) Protection
Add a new test to ORF that would temporarily reject all delivery attempts if the sending IP address is sending to more than "X" (user-configurable) non-existent recipients within in a specified period of time. This would provide some protection against poorly distributed or non-distributed Directory Harvest Attacks.