Email Filtering

Email filtering is the process of evaluating an organization’s inbound and outbound email traffic and determining what to permit and what to deny. Inbound filtering can scan and then organize messages into different categories before delivery to the user’s inbox. Outbound filtering can use the same process before delivering any potentially harmful messages to another organization.

NIST 800-177 Rev 1: Trustworthy Email
This document gives recommendations and guidelines for enhancing trust in email. The primary audience includes enterprise email administrators, information security specialists and network managers. This guideline applies to federal IT systems and will also be useful for small or medium sized organizations.
NIST SP 800-53 Rev 5: SI-8 Spam Protection
NIST resource that defines the requirements for spam protection.

CSO – What are DMARC, SPF and DKIM? How to master email security with these protocols
This article explains the difference DMARC, SPF and DKIM and how to use them to secure you email environment
Fortinet – Spam Filtering
Learn about spam filters, how they work, why they exist, and how to avoid being filtered.
proofpoint – What is Email Filtering?
This article explains the definition, appliances, email filtering techniques, and solutions.

Microsoft – Anti-spam protection in EOP
This document provides anti-spam options information for Office 365 administrators.
SecureOps – What is Layered Security, including Phishing Defense?
This article from SecureOps discusses how organizations can take a layered approach to combat phishing.

Gartner – Email Security Reviews and Ratings
This resource provides a list and reviews of products in the email security market.
SpamTitan – Best Spam Filter for Business
This article looks at the different types of spam filter and the deployment options available.

CMMC Related Controls

Level 1 | SI.L1-3.14.5 – System & File Scanning: Perform periodic scans of the information system and real-time scans of files from external sources as files are downloaded, opened, or executed.

CMMC Assessment Guides

CMMC Level 1 Self-Assessment Guide
This document provides self-assessment guidance for conducting Cybersecurity Maturity Model Certification (CMMC) assessments for Level 1.
CMMC Level 2 Assessment Guide
This document provides assessment guidance for conducting Cybersecurity Maturity Model Certification (CMMC) assessments for Level 2.
CMMC Level 3 Assessment Guide
This document provides assessment guidance for conducting Cybersecurity Maturity Model Certification (CMMC) assessments for Level 3.
NIST SP 800-171A Assessing Security Requirements for Controlled Unclassified Information
The purpose of this publication is to provide procedures for assessing the CUI requirements in NIST Special Publication 800-171.

Resources

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