June Was 'Worst Month Of Malvertising Ever'

Flash zero-days made it easier to deliver ransomware and banking Trojans, and commit click fraud.

June was "the worst month of malvertising basically ever" and Flash zero-day vulnerabilities are partly to blame, says Patrick Belcher, director of security analytics for Invincea. In the first six months of 2015, malvertising was one of the biggest threats to endpoint security, causing an estimated $525 million in damages (related to repair and recovery costs), according to research released today by Invincea.

Invincea says it stopped 2,100 malvertising attacks, all dropping some kind of malware on the endpoint -- mostly ransomware, banking Trojans, or bot code that abuses endpoints for click fraud campaigns.

The researchers identified a Russian threat actor called "Fessleak," that was particularly prolific, and had carried out more malvertising exploits than anyone else Invincea witnessed this year, using real-time ad platforms to deliver ransomare and the Bedep click fraud bot.

"Fessleak was abusing one company so bad he almost ruined the company," says Belcher. The attacker used the ad platform to deliver the Bedep click fraud bot so often that Blue Coat listed the company as a malicious source. They could have gone out of business, had they not succeeded in ejecting Fessleak, says Belcher.

By the end of the year, Belcher expects that the use of weaponized Microsoft Office documents will overtake malvertising as the leading threat, because the use has recently exploded -- with multiple threat actors using the same Visual Basic scripts, available for free on places like Pastebin, to add malicious payloads to documents. The documents are generally delivered via phishing messages.

These malicious documents were used to deliver Dridex, Zeus, Pony, Zbot, Dyreza payloads. They were also used in "just-in-time" malware attacks, which Invincea called the "dominant trend in malare evolution." In such an attack, the malware is delivered to the endpoint in innocent-looking pieces to avoid detection, then assembled on the endpoint, often using native Windows components as part of the finished product.

The researchers also found that although the threat actors behind the Anthem and White House breaches are very sophisticated, the methods they used to invade the organizations were not particularly complex. In fact -- although they may have used custom malware for part of the attack -- the initial intrusions were both accomplished via spearphishing messages with off-the-shelf Trojans attached. In fact, it was the same basic code, just in different wrapping -- the one in the White House was disguised as a video about an office run by monkeys and at Anthem it appeared as a Citrix software update.

See the full report at http://www.invincea.com/1H-2015-threat-report/.

Sara Peters is Senior Editor at Dark Reading and formerly the editor-in-chief of Enterprise Efficiency. Prior that she was senior editor for the Computer Security Institute, writing and speaking about virtualization, identity management, cybersecurity law, and a myriad ... View Full Bio

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