Web Attacks Employing Upgraded Crimeware Kit Hit 1.5 Million Users

The RIG crimeware kit got an upgrade and is the tool of choice in a wave of Web attacks worldwide that is infecting around 27,000 victims each day -- some using an exploit leaked in The Hacking Team breach.

Researchers at Trustwave today reported a spike in use of RIG 3.0, a new version of crimeware kit that was recently updated by its author after the source code was dumped online by a disgruntled underground reseller of the tool. Over the past 6 weeks that Trustwave had monitored the attacks, some 1.25 million users were infected, in series of attacks that mostly came via malicious ads on major websites.

Arseny Levin, lead security researcher at Trustwave, says some 3.5 million users visited those infected sites, and 90 percent of the more than 1 million who were infected were via malicious ads. The attacks--carried out by various groups all employing the shiny new version of RIG, which is typically used as an initial attack vector--used three different exploits, including the Hacking Team's Adobe Flash (CVE-2015-5122) zero-day, which black hat hackers were quick to weaponize before users could patch their machines.

Malvertising -- where ads are injected with malware unbeknownst to the website owner where the ad runs -- is hot. According to a new report from RiskIQ today, malvertising increased 260 percent in the first half of this year. And in sync with the latest RIG 3.0-based attacks: the most number one malvertisement lure is fake Flash updates. Even so, RiskIQ found that fake software updates were more common than exploit kits (think RIG) as the means of installing malware on victims' machines.

Some 3,000 Alexa top 3000 websites -- news, investment consulting, IT solutions providers, and others -- were found harboring the malicious RIG 3.0-rigged ads, according to Trustwave.

In addition to the Hacking Team Flash 0day, the malicious ads also employed the Windows OLE Automation Array exploit (CVE-2014-6332) and a VML attack (CVE-2013-2551) -- all of which are Internet Explorer attacks.

The RIG 3.0-rigged ads were used by various "users or customers" of the crimeware kit for their own attack campaigns, Levin says. "Each was installing a different type of malware on a computer" most using malvertising as the initial attack vector, he says.

Victims were IE users without the latest patches, mainly in Brazil (450,000); Vietnam (300,000); Turkey (82,000); India (62,000); and the US (46,000), at last count.

Aside from malvertising, victims with already-infected machines were reinfected via RIG 3.0, and others, visiting a compromised website, according to Levin.

The most prolific RIG 3.0 attacker has hit more than 100,000 machines was spotted paying other hackers for machines that have not been compromised by the kit before. "However, instead he is actually getting re-infected computers which are more challenging because many are locked out due to ransomware or are not useable for other reasons. This means the customer is getting scammed," Levin wrote in a blog post today. "He is paying ten times more than he should for computers that he thinks are clean but in reality, are not. Typically, customers pay about 10 dollars per 100 infections of clean computers. For an already compromised computer, they pay 10 dollars for every 1000 infections."