A mass compromise that has hit tens of thousands of English-language webpages is probably part of a much larger wave of attacks that's been under way since June by a sophisticated band of criminals, a security researcher said Wednesday.
As reported Monday, the latest mass infection causes websites operated by health-care organizations, charities, and other groups to silently direct visitors to servers that host a potent cocktail of exploits. Since then, the number of pages has grown from about 57,000 to 70,000, said Mary Landesman, a researcher at ScanSafe, a company that protects end users from malicious websites.
Landesman has also discovered that the exploits and registration information for the domain names used in the attack bear a striking resemblance to two other mass compromises, including one from June that seized more than 3 million Chinese pages and exploited a previously unknown vulnerability in ActiveX components provided by Microsoft.
The revelation means the group behind the attacks is probably much better organized than previously believed.
"The fact that this was a compromise campaign to deliver a zero day, at least originally, certainly is cause for concern," Landesman told The Register. "It gives an indication that it is possibly a more sophisticated level of criminal activity. That particular vulnerability was not something that had been widely publicized or known about."
The mass compromise of the Chinese sites remains active, although the number of webpages has fallen to about 100,000.
A separate mass attack in July that compromised about 40,000 webpages of sites, mostly located in India, also bears the hallmarks of the same crew, Landesman said. All of them use SQL injection attacks to plant iframes in pages that, when visited, silently pull down malicious code from websites under the control of the attackers.\
While the exploits are frequently different, similarities in the file names and domain names leads Landesman to conclude they have been perpetrated by the same people.
The analysis comes a day after a Google security researcher said the number of compromised websites the search giant tracks has more than doubled in the first seven months of this year.
On January 1, the number of entries in Google's safe browsing malware list was a little more than 150,000. By the beginning of August, the number had mushroomed to more than 325,000. The list is used to warn users of the Google Chrome, Mozilla Firefox and Apple Safari browsers when they try to visit sites believed to contain malicious exploits. ®