Thursday, May 12, 2005

Telewest Spam Problem

I am posting this, as I know that a lot of people I know use Telewest as their ISP, as indeed I did until my move to Shropshire. Most are probably unaware that they may have their emails "blocked" as spam
Telewest email blocked by spam filters 11:34AM
Cable operator Telewest has had the email addresses of its one million or so Internet customers blacklisted by the anti-spam organisation the Spam Prevention Early Warning System. The organisation says that it has taken the decision to blacklist all of Telewest's Blueyonder customers because so many of them have been hijacked and used as spam servers.
As spam filters have become more sophisticated and their own email servers have been blocked by spam filters, the spammers have turned to other methods to get their messages across. Increasingly this has meant that spammers have turned to the methods used by virus writers to hijack machines with malicious code.

Often hundreds or thousands of machines are recruited into these armies of 'bots' which can be used to generate thousands of email messages. A recent survey says that up to a million PCs have been compromised in this way. Machines are often compromised by a lack of a firewall and antivirus software designed to prevent intrusions.

Spam filters have no way of checking whether these thousands of machines are all legitimate or not. Hence, Spew has used the rather blunt weapon of blocking all of Telewest's email traffic. As a consequence, the move is likely to severely restrict the mail sent out by Telewest's customers.

The SPEW system, used by a range of ISPs and spam filters, checks the sender field of each email. If it comes from an email address known to be sending spam, it is simply blocked.

In a statement, Telewest said 'We are aware of the increase in e-mail volumes due to customers' PCs which have been infected by worms and viruses . We are currently contacting affected customers to help them clean their PCs which, as you can imagine, is a time-consuming task'

The decision is likely to prove an embarrassment to Telewest. After several years of financial woes, the company is finally moving towards its long anticipated merger with rival NTL. What it does not need is customers deserting its broadband service because their mail is bouncing.

I picked up this article from PC pro here

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