Combatting Spam Using Mimedefang, Spamassassin and Perl
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DMARC — Defeating E-Mail Abuse
CERT-EU Security Whitepaper 17-001 DMARC — Defeating E-Mail Abuse Christos Koutroumpas ver. 1.3 February 9, 2017 TLP: WHITE 1 Preface E-mail is one of the most valuable and broadly used means of communication and most orga- nizations strongly depend on it. The Simple Mail Transport Protocol (SMTP) – the Internet’s underlying email protocol – was adopted in the eighties and is still in use after 35 years. When it was designed, the need for security was not so obvious, and therefore security was not incor- porated in the design of this protocol. As a result, the protocol is susceptible to a wide range of attacks. Spear-phishing campaigns in particular can be more successful by spoofing (altering) the originator e-mail address to imper- sonate a trusted or trustworthy organization or person. This can lead to luring the recipient into giving away credentials or infecting his/her computer by executing malware delivered through the e-mail. While raising user awareness on how to avoid e-mail fraud is recommended, the Verizon Data Breach Investigations Report indicates that more needs to be done. The DBIR report reveals that 30% of all phishing e-mail messages were opened by the recipients and with 12% clicked on the content and executed malicious code. The median time for the first user of a phishing campaign to open the malicious email is 1 minute, 40 seconds. The median time to the first click on the attachment was 3 minutes, 45 seconds. These statistics highlight the risk for an organization on the receiving end of spear-phishing e-mails. -
Delivering Results to the Inbox Sailthru’S 2020 Playbook on Deliverability, Why It’S Imperative and How It Drives Business Results Introduction to Deliverability
Delivering Results to the Inbox Sailthru’s 2020 Playbook on Deliverability, Why It’s Imperative and How It Drives Business Results Introduction to Deliverability Every day, people receive more than 293 billion Deliverability is the unsung hero of email marketing, emails, a staggering number that only represents ultimately ensuring a company’s emails reach their the tip of the iceberg. Why? The actual number intended recipients. It’s determined by a host of of emails sent is closer to 5.9 quadrillion, with the factors, including the engagement of your subscribers overwhelming majority blocked outright or delivered and the quality of your lists. All together, these factors to the spam folder. result in your sender reputation score, which is used to determine how the ISPs treat your email stream. Something many people don’t realize is that to the Deliverability is also a background player, so far in the major Internet Service Providers (ISPs) — Gmail, shadows that many people don’t think about it, until Yahoo!, Hotmail, Comcast and AOL — “spam” there’s a major issue. doesn’t refer to marketing messages people may find annoying, but rather malicious email filled with That’s why Sailthru’s deliverability team created this scams and viruses. In order to protect their networks guide. Read on to learn more about how deliverability and their customers, the ISPs cast a wide net. If a works on the back-end and how it impacts revenue, message is deemed to be spam by the ISP’s filters, it’s your sender reputation and how to maintain a good dead on arrival, never to see the light of the inbox, as one, and best practices for list management, email protecting users’ inboxes is the top priority of any ISP. -
Presentations Made by Senders
SES ���� ��� � �� � � � � � � � ������������� DomainKeys ��������� SPF ��������������������� ���������� ����������������� ������������������������������������������������ Contents Introduction 3 Deployment: For Email Receivers 6 Audience 3 Two Sides of the Coin 6 How to Read this White Paper 3 Recording Trusted Senders Who Passed Authentication 6 A Vision for Spam-Free Email 4 Whitelisting Incoming Forwarders 6 The Problem of Abuse 4 What To Do About Forgeries 6 The Underlying Concept 4 Deployment: For ISPs and Enterprises 7 Drivers; or, Who’s Buying It 4 Complementary considerations for ISPs 7 Vision Walkthrough 5 Deployment: For MTA vendors 8 About Sender Authentication 8 Which specification? 8 An Example 8 Conformance testing 8 History 8 Perform SRS and prepend headers when forwarding 8 How IP-based Authentication Works 9 Add ESMTP support for Submitter 8 The SPF record 9 Record authentication and policy results in the headers 8 How SPF Classic Works 9 Join the developers mailing list 8 How Sender ID works 9 Deployment: For MUA vendors 9 How Cryptographic Techniques Work 0 Displaying Authentication-Results 9 Using Multiple Approaches Automatic switching to port 587 9 Reputation Systems Deployment: For ESPs 20 Deployment: For Email Senders 2 Don’t look like a phisher! 20 First, prepare. 2 Delegation 20 Audit Your Outbound Mailstreams 2 Publish Appropriately 20 Construct the record 2 Deployment: For Spammers 2 Think briefly about PRA and Mail-From contexts. 3 Two Types of Spammers 2 Test the record, part 3 Publish SPF and sign with DomainKeys. 2 Put the record in DNS 3 Stop forging random domains. 2 Test the record, part 2 4 Buy your own domains. 2 Keep Track of Violations 4 Reuse an expired domain. -
Account Administrator's Guide
ePrism Email Security Account Administrator’s Guide - V10.4 4225 Executive Sq, Ste 1600 Give us a call: Send us an email: For more info, visit us at: La Jolla, CA 92037-1487 1-800-782-3762 [email protected] www.edgewave.com © 2001—2016 EdgeWave. All rights reserved. The EdgeWave logo is a trademark of EdgeWave Inc. All other trademarks and registered trademarks are hereby acknowledged. Microsoft and Windows are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries. Other product and company names mentioned herein may be the trademarks of their respective owners. The Email Security software and its documentation are copyrighted materials. Law prohibits making unauthorized copies. No part of this software or documentation may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into another language without prior permission of EdgeWave. 10.4 Contents Chapter 1 Overview 1 Overview of Services 1 Email Filtering (EMF) 2 Archive 3 Continuity 3 Encryption 4 Data Loss Protection (DLP) 4 Personal Health Information 4 Personal Financial Information 5 Document Conventions 6 Other Conventions 6 Supported Browsers 7 Reporting Spam to EdgeWave 7 Contacting Us 7 Additional Resources 7 Chapter 2 Portal Overview 8 Navigation Tree 9 Work Area 10 Navigation Icons 10 Getting Started 11 Logging into the portal for the first time 11 Logging into the portal after registration 12 Changing Your Personal Information 12 Configuring Accounts 12 Chapter 3 EdgeWave Administrator -
Set up Mail Server Documentation 1.0
Set Up Mail Server Documentation 1.0 Nosy 2014 01 23 Contents 1 1 1.1......................................................1 1.2......................................................2 2 11 3 13 3.1...................................................... 13 3.2...................................................... 13 3.3...................................................... 13 4 15 5 17 5.1...................................................... 17 5.2...................................................... 17 5.3...................................................... 17 5.4...................................................... 18 6 19 6.1...................................................... 19 6.2...................................................... 28 6.3...................................................... 32 6.4 Webmail................................................. 36 6.5...................................................... 37 6.6...................................................... 38 7 39 7.1...................................................... 39 7.2 SQL.................................................... 41 8 43 8.1...................................................... 43 8.2 strategy.................................................. 43 8.3...................................................... 44 8.4...................................................... 45 8.5...................................................... 45 8.6 Telnet................................................... 46 8.7 Can postfix receive?.......................................... -
Email Sender Authentication Development and Deployment
EMAIL SENDER AUTHENTICATION DEVELOPMENT AND DEPLOYMENT (PROJECT CHEESEPLATE) Volume I Technical and Management Proposal pobox.com IC Group, Inc. [email protected] v1.01 20041217 Full Proposal Control Number EB8A Email Sender Authentication OFFICIAL TRANSMITTAL LETTER IC Group, Inc., a New York State corporation, doing business as pobox.com, respectfully submits a proposal in response to solicitation BAA04-17 for Cyber Security Research and Development. It is submitted under Category 3, Technical Topic Area 7, Technologies to Defend Against Identity Theft, for consideration as a Type II Prototype Technology. Solicitation Title: BAA 04-17 Topic Title: Technologies to Defend Against Identity Theft Type Title: Type II (Prototype Technologies) Full Proposal Control Number: EB8A Proposal Title: Email Sender Authentication A companion proposal, Reputation System Clearinghouse (1RGT), is also being submitted under the same category and type. We request that these two proposals be read together. This proposal should be read first. This proposal was authored by Meng Weng Wong, Founder and Chief Technology Officer for Special Projects. He can be contacted at [email protected]. Meng Weng Wong IC Group, Inc. 1100 Vine St Ste C8 Philadelphia, PA 19107 December 15th 2004 EIN: 113236046 Central Contractor Registration: 3EKUCT Email Sender Authentication 2 EXECUTIVE SUMMARY Pobox.com aims to fight phishing by adding sender authentication “Phishing” is a class of high-tech scam that functionality to the Internet email system. First we will build a library uses fraudulent e-mail to deceive consum- ers into visiting fake replicas of familiar to implement a useful set of recently devised anti-forgery specifica- Web sites and disclosing their credit card tions, including ip-based approaches such as SPF and crypto-based numbers, bank account information, Social approaches such as DomainKeys. -
Canit-PRO User's Guide
CanIt-PRO User’s Guide for Version 10.2.5 AppRiver, LLC 13 September 2018 2 CanIt-PRO — AppRiver, LLC Contents 1 Introduction 13 1.1 Organization of this Manual.............................. 13 1.2 Definitions........................................ 14 2 The Simplified Interface 19 3 The My Filter Page 21 3.1 Sender Rules...................................... 21 3.2 The Quarantine..................................... 22 3.3 Online Documentation................................. 22 4 The CanIt-PRO Quarantine 23 4.1 Viewing the Quarantine................................. 23 4.1.1 Message Summary Display........................... 23 4.1.2 Sort Order.................................... 24 4.1.3 Message Body Display............................. 25 4.1.4 Summary of Links............................... 25 4.2 Message Disposition.................................. 25 4.2.1 Quick Spam Disposal.............................. 26 4.3 Reporting Phishing URLs................................ 27 4.4 Viewing Incident Details................................ 27 4.4.1 Basic Details.................................. 28 4.4.2 Address Information.............................. 29 4.4.3 History..................................... 29 4.4.4 Spam Analysis Report............................. 29 4.5 Viewing Other Messages................................ 30 4.6 Viewing Specific Incidents............................... 30 CanIt-PRO — AppRiver, LLC 3 4 CONTENTS 4.7 Searching the Quarantine................................ 30 4.8 Closed Incidents.................................... -
How to Make Sure Your Emails Land in Your Prospects' Inboxes
How to Make Sure Your Emails Land in Your Prospects’ Inboxes How to Make Sure Your Emails Land in Your Prospects’ Inboxes | 1 Table of Contents Why Aren’t My Emails Getting Through? 3 Authentication 5 Permissions 7 Reputation 9 Sender Reputation 9 Cleanliness & Monitoring 10 List Source 10 New Domain Address Warming 11 Review Bounces 14 Monitoring Blacklists 15 Follow the Rules - CAN-SPAM, CASL, GDPR & CCPA 16 Engagement 17 Know Your Audience - Relevance, Frequency & Content Review 17 Unsubscribe Links 18 Conclusion 19 How to Make Sure Your Emails Land in Your Prospects’ Inboxes | 2 Why would my emails never make it to their destination? As we move further into the era of technology, email has become the primary source of professional communication. As a result, bad actors are doing whatever it takes to get you to view their emails. How many members of the Nigerian royal family have contacted you to transfer their fortune to your bank account? In response to more frequent attempts to phish, hack, and send spam, Internet Service Providers (ISPs) are doing everything they can to protect their customers from potentially unsolicited email, ! including blocking bulk email sends from new domains and internet protocol (IP) addresses. It’s important to remember that ISPs are always looking to protect their users (and investors). Because you’re sending emails to reach out to your prospects, these new measures have a direct impact on your ability to have your legitimate emails delivered to the inbox. How to Make Sure Your Emails Land in Your Prospects’ Inboxes | 3 Ultimately it is the practices of your company, and your engagement strategy, that determines whether or not your messages get through. -
Guide Deliverability.Pdf
email delivery for IT professionals INTRODUCTION................................................................................................................................................ 3 HOSTING AND HARDWARE ............................................................................................................................... 4 IP/DNS ............................................................................................................................................................. 5 DNS Naming................................................................................................................................................ 5 I already have a domain.......................................................................................................................... 5 I'm sending on behalf of someone else................................................................................................... 5 I'm sending on behalf of several companies............................................................................................ 6 IP Ranges .................................................................................................................................................... 6 Test IPs ....................................................................................................................................................... 6 Registrars................................................................................................................................................... -
Canit-Domain-PRO Administration Guide for Version 10.2.9 Appriver, LLC 11 December 2020 2
CanIt-Domain-PRO Administration Guide for Version 10.2.9 AppRiver, LLC 11 December 2020 2 CanIt-Domain-PRO — AppRiver, LLC Contents 1 Introduction 19 1.1 Principles of Operation................................. 19 1.2 Handling False-Positives................................ 19 1.2.1 Spam-Control Delegation........................... 20 1.3 Organization of this Manual.............................. 20 1.4 Definitions........................................ 21 2 Operation 27 2.1 Principles of Operation................................. 27 2.2 Interaction between Allow Rules and Block Rules................... 28 2.2.1 RCPT TO: Actions............................... 28 2.2.2 Post-DATA Actions............................... 30 2.3 Streaming........................................ 32 2.4 How Addresses are Streamed.............................. 32 2.5 How Streaming Methods are Chosen.......................... 33 2.6 Status of Messages................................... 35 2.6.1 Secondary MX Relays............................. 36 2.7 The Database...................................... 36 2.8 Remailing Messages.................................. 37 3 Realms 39 3.1 Introduction to Realms................................. 39 3.2 Realm Names...................................... 40 3.2.1 The base Realm................................ 40 3.3 Creating Realms..................................... 40 3.4 Realm Mappings.................................... 41 3.5 Determining the Realm................................. 42 CanIt-Domain-PRO — AppRiver, LLC 3 4 CONTENTS -
Clam Antivirus 0.88.2 User Manual Contents 1
Clam AntiVirus 0.88.2 User Manual Contents 1 Contents 1 Introduction 6 1.1 Features.................................. 6 1.2 Mailinglists................................ 7 1.3 Virussubmitting.............................. 7 2 Base package 7 2.1 Supportedplatforms............................ 7 2.2 Binarypackages.............................. 8 2.3 Dailybuiltsnapshots ........................... 10 3 Installation 11 3.1 Requirements ............................... 11 3.2 Installingonashellaccount . 11 3.3 Addingnewsystemuserandgroup. 12 3.4 Compilationofbasepackage . 12 3.5 Compilationwithclamav-milterenabled . .... 12 4 Configuration 13 4.1 clamd ................................... 13 4.1.1 On-accessscanning. 13 4.2 clamav-milter ............................... 14 4.3 Testing................................... 14 4.4 Settingupauto-updating . 15 4.5 Closestmirrors .............................. 16 5 Usage 16 5.1 Clamdaemon ............................... 16 5.2 Clamdscan ................................ 17 5.3 Clamuko.................................. 17 5.4 Outputformat............................... 18 5.4.1 clamscan ............................. 18 5.4.2 clamd............................... 19 6 LibClamAV 20 6.1 Licence .................................. 20 6.2 Features.................................. 20 6.2.1 Archivesandcompressedfiles . 20 6.2.2 Mailfiles ............................. 21 Contents 2 6.3 API .................................... 21 6.3.1 Headerfile ............................ 21 6.3.2 Databaseloading . .. .. .. .. .. . -
Adoption of Email Anti-Spoofing Schemes: a Large Scale Analysis
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/TNSM.2021.3065422, IEEE Transactions on Network and Service Management IEEE TRANSACTIONS ON NETWORK AND SERVICE MANAGEMENT 1 Adoption of Email Anti-Spoofing Schemes: A Large Scale Analysis Sourena Maroofi, Maciej Korczynski,´ Arnold Hölzel, Andrzej Duda, Member, IEEE Abstract—Sending forged emails by taking advantage of a real Microsoft login page to steal user credentials [2]. In this domain spoofing is a common technique used by attackers. paper, we investigate the second type of email spoofing. The lack of appropriate email anti-spoofing schemes or their The Simple Mail Transfer Protocol (SMTP) for email dis- misconfiguration may lead to successful phishing attacks or spam dissemination. In this paper, we evaluate the extent of tribution does not provide support for preventing spoofing [3] the SPF and DMARC deployment in two large-scale campaigns so mail systems need to rely on security extensions such as measuring their global adoption rate with a scan of 236 million the Sender Policy Framework (SPF) [4], the DomainKeys domains and high-profile domains of 139 countries. We propose Identified Mail (DKIM) [5], and Domain-based Message Au- a new algorithm for identifying defensively registered domains thentication, Reporting, and Conformance (DMARC) [6] to and enumerating the domains with misconfigured SPF rules by emulating the SPF check_function. We define for the first time authenticate the sender and decide what to do with suspicious new threat models involving subdomain spoofing and present emails.