| Study: Image spam levels rocket
Image spam levels have soared over the past six months, now accounting for over half of all spam, according to new research. Figures released by Marshal show that image spam has jumped by 175 percent since September last year, representing 56 percent of all spam sent over the past six months.This rise in picture-based spam coincides with the decline of messages containing embedded URL links, the study claims. In 2004, 96 percent of spam messages included a website hyperlink for the recipient to click. This figure has dropped to just over half, according to the research.Spammers are constantly morphing their practices to overcome anti-spam filters, said Bradley Anstis, director of product management for Marshal. And we can expect image spam levels to continue to increase this year.
Write TMDA filters for spam-handling
Vincent Danen revisits the TMDA spam handler. He champions the effectiveness of the challenge/response mechanism with the addition of custom filters that you can write yourself. In a previous tip, I introduced TMDA (Tagged Message Delivery Agent) as a great way of reducing unsolicited (spam) e-mail. While some people disagree with the challenge/response method of handling e-mail, citing that all it does it create more unsolicited e-mail, tools like TMDA are 100 percent effective through the use of white and black lists, filtering and, of course, the challenge/response mechanism itself. You may prefer filtering with a tool such as procmail, as it is far more flexible, but within the framework of TMDA itself, you can create filters that do particular actions based on the filter expression.
Cisco Buys IronPort
Cisco today turned its security strategy in a new, application-oriented direction, acquiring messaging security vendor IronPort Systems for $830 million in cash and stock. IronPort, a five-year-old, privately held company, makes appliances for Web security and management, but it is best known for its email security appliances, which help filter spam and detect malware in large and small enterprises as well as Internet service providers. Eight of the top 10 ISPs, as well as large enterprises such as JetBlue Airways, are IronPort users. The move is something of a departure for Cisco, which has acquired many security vendors over the years but has generally kept those acquisitions focused on targets that operate at the network level. Experts say today's move could indicate that the company is shifting its considerable weight toward a broader role in the security industry, just as software giant Microsoft has done.
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