How Spammers Fool Spam Blacklists - And How to Stop Them

Effectively stopping spam over the long-term requires much more than blocking individual IP addresses and creating rules based on keywords that spammers typically use. The increasing sophistication of spam tools coupled with the increasing number of spammers in the wild has created a hyper-evolution in the variety and volume of spam. The old ways of blocking the bad guys just don't work anymore.

Examining spam and spam-blocking technology can illuminate how this evolution is taking place and what can be done to combat spam and reclaim e-mail as the efficient, effective communication tool it was intended to be.

One method used to combat spam is blacklisting. The goal of blacklisting is to force Internet Service Providers (ISPs) to crack-down on customers who send spam. A blacklisted ISP is blocked from sending email to organizations. When an ISP is blacklisted, they are provided with a list of actions they must take in order to be removed from the blacklist. This controversial method blocks not just the spammers, but all of the ISP's customers. Blacklisting is generally considered an unfriendly approach to stopping spam because the users most affected by the blacklist are email users who do not send spam. Many argue blacklisting actually damages the utility of email more than it helps stop spam since the potential for blocking legitimate email is so high.

In addition to the ethical considerations, there are other problems with blacklists. Many blacklists are not updated frequently enough to maintain effectiveness. Some blacklist administrators are irresponsible in that they immediately block suspect servers without thoroughly investigating complaints or giving the ISP time to respond. Another downside is that blacklists are not accurate enough to catch all spam. Only about half of servers used by spammers, regardless of how diligent the blacklist administrator may be, are ever cataloged in a given blacklist.

Blacklists are used because they can be partially effective against spammers who repeatedly use the same ISP or email account to send spam. However, because spammers often change ISPs, re-route email and hijack legitimate servers, the spammer is a moving target. Blacklist administrators are forced to constantly revise lists, and the lag-time between when a spammer begins using a given server and when the blacklist administrator is able to identify the new spam source and add it to the blacklist allows spammers to send hundreds of millions of emails. Spammers consider this constant state of flux a part of doing business and are constantly looking for new servers to send spam messages.

When used individually, each anti-spam technique has been systematically overcome by spammers. Blacklists have some utility in stopping known spammers, but they may also block valid emails. Because of their limitations, blacklist data should only be used in conjunction with other sources to determine if a given message is spam. Grandiose plans to rid the world of spam, such as charging a penny for each e-mail received or forcing servers to solve mathematical problems before delivering e-mail, have been proposed with few results. These schemes are not realistic and would require a large percentage of the population to adopt the same anti-spam method in order to be effective.

The Solution

Reputation systems offer a comprehensive anti spam solution by dynamically updating black and whitelists based on sender behavior. These systems also automatically update and score messages thereby removing the burden from administrators. Today's spammers are more clever than ever, so today's reputation systems must be equally sophisticated. An effective reputation system must be dynamic, comprehensive, precise, and based on actual enterprise mail traffic in order to keep the spammers from gaining any advantage. You can learn more about the fight against spam by visiting our website at www.ciphertrust.com and downloading our whitepapers.

Dr. Paul Judge is a noted scholar and entrepreneur. He is Chief Technology Officer at CipherTrust, the industry's largest provider of enterprise email security. The company's flagship product, IronMail provides a best of breed enterprise anti spam solution designed to stop spam, phishing attacks and other email-based threats. Learn more by visiting enterprise anti spam solution today.

emergency cleaning services Glencoe ..
In The News:

The iconic Mary Kay pink Cadillac goes electric with the Cadillac Optiq, available only to the company's top 1% of sales force performers.
Cybercriminals abuse trusted Intel driver to gain kernel access and shut down Windows Defender, enabling undetected malware deployment since July 2025.
Using email aliases for online shopping and subscriptions can protect your privacy by preventing companies from linking your activity across websites.
New research shows AI overlap does not equal job replacement, with knowledge-based roles seeing most integration while physical jobs remain least affected.
Scammers target seniors who avoid social media by exploiting public records like obituaries and real estate filings to steal personal information and money
Recovery team in Italy use AI-enabled drones to detect missing hiker's red helmet, leading to successful recovery after months of ground searches
Google Salesforce system breach exposes business data while scammers use incident to target users with fake security calls and phishing attempts.
Google announces Pixel 10 lineup with Tensor G5 chip and Gemini Nano AI, introducing Magic Cue, Pro Res Zoom up to 100x and satellite emergency support features.
C San Diego study reveals 86% of school safety companies monitor students 24/7 on personal devices, raising privacy concerns.
Users can now add their favorite outlets' coverage to the Top Stories section of Google search results by utilizing the 'preferred sources' feature. With just a few clicks, you can add Fox News.
Stay up to date on the latest AI technology advancements and learn about the challenges and opportunities AI presents now and for the future.
Interstellar object 3I/ATLAS shows an unexpected frontal glow that Harvard's Avi Loeb says cannot be explained by sunlight reflection or standard cometary outgassing.
Receiving order confirmations for purchases you never made could mean your email address is being exploited in fraud operations targeting multiple retailers.
First wireless brain implant works with Apple's official protocol, enabling hands-free control of iPhones, iPads and Vision Pro through thought alone.
Data brokers sell personal details that scammers use to target retirement funds through fake financial advisor calls and convincing phishing attempts
Ten innovative tech solutions from gait sensors to smart pill dispensers help adults 65+ track fall risks and prevent injuries before they happen.
Meta AI internal documents revealed chatbots were allowed to flirt with children and engage in romantic conversations until the company was exposed by Reuters.
ChatGPT will avoid giving direct mental health advice under new OpenAI rules following instances where the AI model provided harmful or misleading responses.
Your phone tracks you in more ways than that little GPS icon suggests. Here’s how to find and clear hidden location logs on iPhone and Android.
Authorities in France and the Netherlands have been notified. Meanwhile, impacted customers are being told to stay alert.
Apple just rolled out a redesigned Blood Oxygen feature to specific models, following a recent victory in a legal dispute.
Kidney dialysis provider DaVita experienced a ransomware breach by the Interlock gang affecting 916,000 people in the second-largest U.S. healthcare attack of 2025.
A Chinese-made Unitree R1 robot walked Manhattan streets and shopped for shoes as part of KraneShares' $28 million AI robotics fund promotion campaign.
The ShinyHunters cybercriminal group breached Google's Salesforce system through vishing attacks, stealing business contact details and customer data.
Stay up to date on the latest AI technology advancements and learn about the challenges and opportunities AI presents now and for the future.

How Spammers Fool Spam Blacklists - And How to Stop Them

Effectively stopping spam over the long-term requires much more than... Read More

How Spammers Fool Rule-based and Signature-Based Spam Filters

Effectively stopping spam over the long-term requires much more than... Read More

How Spammers Fool Whitelists - And How to Stop Them

Effectively stopping spam over the long-term requires much more than... Read More

I Must Be The Luckiest Person Alive! Spam

I must be the luckiest person alive! My inbox is... Read More

Dont Look Spammy!

We all hate spam and get way too much of... Read More

Spam - How to Report it

I'm sure you find spam just as frustrating and annoying... Read More

All About Spam

Spam is annoying. Period. Why people would want to send... Read More

Internet Tip of the Week: Outsourcing

It's no secret that the US economy has slowed down,... Read More

Customers Demand Internet Privacy

... and you'd better sit up and take notice! Customers... Read More

Demand for Spam? It exists

Do you like spam? No, I'm not kidding. Everybody knows... Read More

Internet Tip of the Week: Information Overload

We receive so much information on the Internet, especially via... Read More

Getting Back To Basics.

While we all agree that there`s way too much spamming/junk-mailing... Read More

SPAM: A Nutrious Food or a Waste of Time?

Unless the filters on your computer are really good, you're... Read More

Spam - Its Whats For Breakfast

The first thing I do every morning when I wake... Read More

How You Can Avoid The New Dangers Of Spam

Until recently, spam has been an annoyance, a definite load... Read More

Corporate Email Policies Lower Unnecessary Legal and Security Risks

What comes to your mind when you think about your... Read More

How To Identify Spam

Most of us have opened our email program and found,... Read More

Three Faces of SPAM

Like everybody who will ever read this, I get spam... Read More

Email Chain Letters - Harmless Fun or Not?

I'm sure I'm not the only person on the planet... Read More

How Can I Stop Getting Spam?

Are you getting too much spam? We all are, but... Read More

Bayesian Spam Filters Explained

In a word Bayesian spam filters are "intelligent". Bayesian spam... Read More

Challenge Response Spam Filters Explained

As the flood of spam increases end users are looking... Read More

How Spammers Fool Bayesian Filters - And How to Stop Them

Effectively stopping spam over the long-term requires much more than... Read More

5 Zero-Cost Spam Prevention Tools For All Situations!

Anyone who uses email knows what Spam is!It's annoying and... Read More

Stop Spam: How To Escape The Spam Hell-Hole

If you're anything like me, you're pretty sick of it,... Read More

trusted cleaning company Wilmette ..