The biggest change we have seen over the last three years is the rise in the web as a significant weapon in the cybercriminals’ armory. Now an indispensable business tool, the web is still a relatively unprotected route to the users’ desktops and laptops. Once infected, these compromised computers can be used to steal confidential data and trade secrets or to spam out millions of emails. The real change is the way in which users’ computers are infected
Previously, virus writers relied on a user downloading an infected file (which would probably have been detected and blocked by desktop anti-virus anyway).
Infected email attachments sent directly to users proved to be the bigger threat. Today, spyware and other malware is placed on a website and users are lured to the compromised webpages via spammed email invitations. The type of website is immaterial: gardening and cookery websites are as likely to be infected as gambling or pornography sites.
The number of infected Web pages has rised nearly six-fold since the first of the year, according to security company Sophos.
Detailed in a just-released threat report, the spike shows just how widespread Web attacks have become, Sophos said Wednesday. In June, it detected an average of almost 30,000 newly-infected pages each day; earlier in the year, the count was as low as only 5,000 new pages daily.
The vast majority of pages serving up malicious content are, in fact, hosted on legitimate Web sites, Sophos also said. About 80 percent of all Web-based malware is on innocent, albeit compromised, sites.
A recent example: The June attacks launched from a collection of more than 10,000 legitimate Web sites, the bulk of them hosted on Italian servers. The servers were compromised using an unknown vulnerability, then loaded with Mpack, a multiple-exploit toolkit hackers deploy to hijack PCs visiting those sites.
"It begs the question as to why Web hosts are not taking the necessary steps to properly secure their servers," said Graham Cluley, senior technology consultant at Sophos, in a statement. "Simple measures such as keeping up to date with security patches will go a long way towards thwarting this problem; the fewer holes in server setups, the lower the risk of infection.
"Hosts not behaving responsibly must bite the bullet and take better care of their sites."
Just over half -- 51 percent -- of the infected sites are on servers powered by Apache, the open-source Web server software, Sophos reported. Microsoft's IIS (Internet Information Services) Web server, meanwhile, accounted for 34 percent of compromised or malicious systems. Both numbers are in line with Web server market share, according to the U.K.-based Internet measuring company Netcraft Ltd. Its figures put Apache at 50 percent of all servers, IIS at 35.5 percent.
"Malware is not just a Microsoft problem," Cluley said.
The Italian incident, he continued, is a textbook example of a threat that targets and exploits all kinds of vulnerable sites, not just the usual suspects. "Web security solutions must go beyond blocking sites based simply on category. A gambling site may seem more of a threat, but sometimes the most innocuous sounding site can pose the greatest danger."
Sophos' threat report is available online. |
