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Email & Spam

Security Topics


Email Spam

Zero Day Window


Bayesian Algorithm

Content and Connection control

Directory Harvesting Attacks

Email Encryption

Email Archiving

File attachments

Image scanning

Port forwarding and MX records

Reputation filters

Encrypted attachments

Grey Listing

Email Monitoring

Internal Email Security

Open Relay

Per user quarantine area

Reverse DNS lookup & SPF

RFC Compliant emails


Email Throttling

What is Spam

Whitelists and Blacklists



Scanning of Email File Attachments for Malicious Threats


Files such as spreadsheets and word documents make it easier to hide malicious code. An anti-spam security solution should be capable of completely breaking these down, analysing all components and identifying all threats. The purpose of an anti-spam solution offers deep recursive analysis technology that is able to break down all container files, analysing each one independently and taking appropriate action via its security policies.

Zipped attachments are commonly used in order to compress files to smaller sizes. Zipped files can contain any type of files, possibly including file types not allowed through the anti-spam security solution. For anti-spam security solutions, it is a key feature to be able to unzip a file no matter how deeply nested it is, and checked for all of its content against its security policies. Also attachments such as Word documents can contain malicious embedded objects such as macros, html links, java scripts other scripts which anti-spam solutions should be able to pick up on and analyse this type of content for malicious threats as well.

Further Reading

Wikipedia's guide to Email Attachments