Paul lives in Brisbane, Australia and works as a technical consultant for a national IT services provider, specialising in Microsoft Exchange Server and related messaging systems.
A highly desirable goal of businesses and web users is the complete eradication of spam from the internet. That is perhaps a bit too much to hope for, but certainly the goal of reducing spam is something we can all keep working towards.
One of the more effective methods of reducing spam in recent years is through IP filtering. This technique involves checking the IP address of the computer or server that is trying to send you email against a list of known or highly suspect spam sources. The lists are provided by various third party organizations such as Spamhaus and are typically integrated into the products sold by security vendors.
The best part of this technique is that the check occurs at the earliest stage of the initial communication between the two servers. If the IP address is considered to be a spam source then the connection is terminated before time and server resources are wasted by accepting any further part of the email content.
This meant greater efficiency in spam protection systems compared to earlier techniques that involved checking the entire message content for certain keywords or strings that matched a database of known spam. This technique is still used today, but it is only performed on email that first passes the IP filtering checks.
Some estimates put the amount of spam that is typically stopped by IP filtering at around 80-90%. That is up to 90% of spam (not of total email traffic) that can be prevented by IP filtering, usually with very few false positives.
The remaining 10-20% poses a bigger challenge. These emails need to be checked more thoroughly for other characteristics such as:
- Sender address/domain
- Email body content such as text or URI (Uniform Resource Identifier, often called a URL by web users)
- Images and file attachments
This is because spam emails can come from trustworthy sources such as webmail providers and ISPs in which specific accounts have been compromised by a phishing attach. As a result they cannot be blocked reliably on the basis of sender address/domain. Continue reading Could Better URI Filtering Cure Email Spam?
Virtualization has been a growing trend in business computing over the last few years. Companies are able to use virtualization to reduce costs and improve efficiency. What started at the server level is also infiltrating desktop computing, with virtualized desktops now showing up in a lot of environments.
Another recent trend has been the appearance of botnets that have the ability to detect when they are being studied by security researchers. Often this study is taking place using honey pots, which are fake systems set up by researchers to be deliberately infected with malware so that they can study its behaviour.
This has lead some security experts to predict that soon it will be common for botnets to actively look for the signs of a honey pot and either deactivate those systems, or perhaps even generate DDOS attacks against the researchers.
The CTO of database security firm Imperva, Amichai Shulman, suggests that “Most honeypot machines are based on a virtualization platform (most often VMWare). By detecting this attribute of the infected platform, malware developers will probably be able to detect most honeypots out there.”
The intersection of these two trends could have a positive outcome for businesses concerned about botnets infecting their corporate systems. If botnets actually did begin shutting down when virtualization platforms were detected, then the use of virtual desktops could in itself prevent a botnet from becoming active. Continue reading Will Virtualization Protect Businesses from Botnet Infection?
The Messaging Anti-Abuse Working Group (MAAWG) has released new figures that put the average volume of email spam on the internet at 90%, peaking as high as 94.2% in recent years.
Jerry Upton, MAAWG Executive Director said “We’ve been sitting at a stalemate for probably two to three years. Taking out the highs and lows, we’re sitting at about 90%”.
Figures that regularly appear from various security vendors have been telling the same story for several years now. With latest figures confirming the continuing trend one might be forgiven for wondering who is really winning the war against spam.
Spam fighting is a multi-billion dollar industry and businesses are spending thousands or even millions of dollars each year to try and protect their networks from spam threats.
Network providers have had some successes by disconnecting major spam networks from the internet but in most cases the spammers have resurfaced or simply distributed their infrastructure across international jurisdictions.
Consumer ISPs are generally against implementing measures to prevent their customers from adding to the problem. This despite MAAWG’s findings that “tens of millions of Web users in North America and Western Europe have clicked on spam at least once – and many of them did it on purpose”. Continue reading The Spam Statemate
The security of social networks was thrust into the spotlight yet again this week with the successful hack of the Twitter Grader application run by Hubspot, a maker of social media and internet marketing tools.
The Twitter Grader application uses an algorithm to calculate, or grade, a Twitter user’s ranking among their peers. This type of tool has been very popular with Twitter users who willingly grant access to their Twitter accounts for websites that offer this type of ego-feeding information.
The compromise resulted in thousands of unauthorized messages being sent from Grader users’ Twitter accounts containing a link to a web page that hosted an embedded video. The content turned out to not be malicious and it has been speculated that this was an attempt to increase the search engine rankings of the website.
The hack was quickly acknowledged by Hubspot who proceeded to take down the Grader application while they investigated the issue. Grader users are advised to revoke access for Grader to their Twitter accounts and also to consider changing their account password. Continue reading Twitter Grader Hack Highlights Social Network Spam Risks
There have recently been two publicized, high profile attacks on email marketing services. The two services are Aweber and iContact, each confirming the attacks within about a month of each other.
These companies, and many others like them, provide email marketing services to websites and other online businesses. Email marketing, when done properly, is a legitimate practice and is not spam although some people do not make the distinction between the two.
A legitimate email marketing service will require a subscriber to deliberately opt-in to a list, usually by sending them a confirmation email before they are added to a marketer’s email list. This stops spammers from simply harvesting email addresses, importing them into one of these services, and starting to spam them.
This opt-in requirement, plus other measures, assures a high deliverability rate for the customers of the email marketing service because antispam systems on the receiving end can have a high level of confidence that the marketing messages are opt-in and not spam.
Among the more paranoid web users there is a tendency to use unique emails for each mailing list that they sign up to. So if they were to sign up to ABC Corp’s mailing list, they would use paul_abc@somewhere.com, and then for XYZ Pty Ltd would use paul_xyz@somewhere.com.
This might seem like a lot of hassle to go to, generating unique email addresses for every list you subscribe to, but when the attacks on these companies occurred it was these people who noticed the problem first. Suddenly their secret, unique addresses began receiving pharmaceutical spam emails. Your average person who uses one single email address probably would not have noticed this additional spam.
Initial reports were sketchy but eventually first Aweber, and then later iContact determined that a data breach had occurred in their systems. In both cases the outcome was the same – subscriber email addresses were compromised, but customer account and billing information was not. Continue reading Email Marketing Services Targetted by Hackers
A survey conducted recently found that businesses are experiencing a 70% increase in spam and malware attacks from social networks in the last year.
Over half of the 500 companies received spam via a social network, and more than one third experienced a malware infection from one of these sites.
The perception is growing among businesses that social networks are a risk of more than just employees wasting time. Most companies either take a blanket allow or deny approach to social networks but apply no other measures to address the larger risks that these websites expose them to.
Spam and phishing are rampant on the most popular networks such as Twitter and Facebook. For all the attention paid to email security for businesses, often very little is given to the messaging capabilities of social network sites. Clicking on a malicious link in a Twitter message is no different to the same link delivered via email. From the spammer’s perspective the deliverability rate of their messages is much higher on social networks than it is for email.
These attacks continually come to light in the media. Twitter has notified some users that they may have been subjected to a phishing attack and has forced them to update their passwords to ensure their accounts are not misused. This reactionary step is the closest thing to protection that can be achieved on an unmoderated medium like Twitter that has no entry requirement other than a working email address, and exposes a rich API that is perfect for spam automation systems. Continue reading Social Network Spam Continues to Rise, Businesses Feeling Impact
A research team from two Californian universities has developed what it believes will be a game changing approach to defeating spam.
The researchers used a captured spam bot to analyze a sample of the spam emails that it produced and then used this information to reverse engineer the template that the spam emails were based upon. Once this template was known 100% of further spam emails from that bot were successfully blocked while avoiding any false positives on one million genuine email messages in the test.
Leading anti-spam products in the market today claim up to 99% accuracy for spam detection and use sophisticated analysis techniques such as Bayesian filtering to reduce false positives. However a large part of the fight against spam remains reactive.
Continue reading Researchers Analyze Bots to Beat Spam, But Will it Work?
British ISPs have reacted strongly to the suggestion of Trend Micro CTO David Rand that the ISPs should actively combat the problem of spam on the internet.
Rand’s suggestion is the blocking of TCP port 25 (the port used for SMTP, or email, communications between servers on the internet), making contact with customers who they suspect may be the source of spam outbreaks, as well as stronger government legislation.
The legislation idea has merit, after all the lack of cooperation between government agencies is how many international spam operations manage to go unpunished. The blocking of SMTP on the other hand is impractical and costly to implement, both from a technical and a service perspective.
The basis of the idea is this. Customers send mail using SMTP, therefore by blocking SMTP and requiring that customers send mail via the ISP’s mail servers allows close monitoring of email traffic and detection of spam.
The solution is problematic though because many ISP customers, both home users as well as businesses, have perfectly good reasons to not send their email via their ISPs mail servers. These customers would need to be unblocked from using SMTP, and hence cannot be closely monitored.
The monitoring itself also presents two problems – firstly customers object to having their email correspondence inspected by other parties including their ISP. Secondly, any false positives could have disastrous consequences if important emails were blocked. ISPs do not want the exposure to liability if they block an email that results in monetary loss for the sender or recipient. Continue reading ISPs Don’t Want to be Spam Cops
The last few years have seen a sharp rise in the power and features of smart phones such as the Blackberry, Apple iPhone, and most recently Google Android-based phones.
Coupled with this rise is a new ecosystem of mobile application development, made mainstream by Apple’s App Store for the iPhone which boasts over 30,000 applications available for download.
This trend has reached a new, troubling milestone with the discovery of several fraudulent banking applications on the Google Android online store. The programs were disguised as genuine mobile banking applications and were designed to steal online banking credentials from anyone using them.
Although the applications have now been removed it highlights the constant evolution of the security threat landscape. As technology becomes more ubiquitous it extends the threats in what are frankly quite predictable directions, at least for the security-minded among us. Continue reading Phishing and Malware in the Smart Phone Era
Business Week reports that a study by researchers in New York reveals that as many as one in five young, overweight people have been a victim of email spam.
The study revealed some interesting statistics:
- 88% of overweight individuals reported receiving spam pitching weight loss products, compared to 73% of other respondents
- 42% of overweight individuals said they opened the spam, compared to 18% of other respondents
- 18% of overweight individuals said they bought products promoted in the emails, compared to just 5% of other respondents
Firstly why do overweight people receive more weight loss spam? One theory is that these people are visiting more web sites on that topic than other people, and therefore end up in marketing databases. This means that the spam is either coming from the website owner, or another party that is given access to the database of email addresses. This access may be either from selling the list or by using co-registration, which is a legitimate lead-sharing strategy that is often abused by spammers.
For any email marketer a 42% open rate is outstanding. It means that the subject line for the email was very effective at enticing the recipient to open the email and read more.
For a spammer sending 1,000,000 emails 42% open rates do not mean 420,000 people opened them. Most of those recipients will never receive the spam due to anti-spam protection on their email server or their computer. But even a 1% penetration could mean several thousand people open the email.
Finally the conversion rate for overweight people is very good at 18%. Several hundred conversions of a weight loss product likely to cost $50-$200 is a good day’s pay for the spammer. Continue reading Weight Loss Scams Reveal Why Spam Works


