Darkleech is targeting Java and Adobe vulnerabilities to spread the Reveton ransomware which is now responsible for compromising thousands of websites has resurfaced.
Security firm FireEye reported being alerted to the latest wave of Darkleech attacks in a public blog post after its own web url was the target of the attack. “We were notified by several security researchers that a fireeye[.]com/careers HR link was inadvertently serving up a drive-by download exploit,” the post said.
“It turns out, this attack was not targeted and it was not a watering hole attack. Instead, this campaign appears to be a recent wave of the Darkleech malware campaign, where third-party Horde/IMP Plesk Webmail servers were vulnerable to attack and used to serve up Java exploits that ultimately drop yet another ransomware named Reveton (similar to Urausy).”
The attack is a development on the traditional Darkleech operation, and uses a multi-stage process to redirect users to malware-ridden websites.
“Darkleech itself is mainly responsible for getting you to the page that does the actual exploitation,” said Josh Gomez, malware research engineer at FireEye.
“The next stage is where the actual attack takes place, systems become exploited and subsequently infected,” he said. “The URL that Darkleech tries to get the victim to load is typically that of a site hosting the Blackhole Exploit Kit. The Blackhole Exploit Kit is a professional framework for automatically exploiting weaknesses in vulnerable browsers, as well as vulnerable versions of Java and Adobe software, such as Adobe Reader.”
Gomez said the new attack will likely be a pain for businesses, as the infection method can circumvent traditional cyber defenses and can spread other malware when combined with tools such as the Blackhole Exploit Kit.
The researcher said businesses should to be extra vigilant with their update cycles and reassess whether they need to run Java.
To defend against this sort of attack, enterprises and users should maintain up-to-date versions of web browsers as well as Java and Adobe reader versions. If a user does not need Java, simply disable it which will mitigate Java-based attacks. Also, having up-to-date perimeter security solutions as well as host antivirus and intrusion prevention systems on the endpoint itself can help prevent falling victim, he said.
Darkleech is a malicious module designed to target Apache (web) servers.