Attackers are taking advantage of old vulnerabilities

FortiGuard Labs observed a 30 percent increase in mobile malware in the labs over the last six months. The team is now seeing more than 1,300 new samples per day, is currently tracking over 300 unique Android malware families and over 250,000 unique malicious Android samples.

“Three years ago, mobile malware wasn’t much of a concern for users or businesses. Most malware at the time targeting smartphones and tablets were nothing more than annoyware such as the Cabir virus or scam software used to commit SMS fraud or replace icons,” said Axelle Apvrille, senior mobile anti-virus researcher for Fortinet’s FortiGuard Labs. “However, as devices have proliferated, so, too, have cybercriminals eager to capitalize on the growing user base, and our research shows the proliferation of mobile malware will not abate anytime soon.”

Ransomware has been incredibly successful financially for cybercriminals, it’s no surprise they’ve turned their attention to mobile devices,” said Richard Henderson, security strategist for Fortinet’s FortiGuard Labs. “The Fake Defender malware for Android follows the same M.O. as PC fake antivirus software – it pretends to be altruistic, but in reality, it lies in wait to launch its true form. This malware then locks the victim’s phone and demands payment before unlocking the device. Once the phone is locked, the victim can either pay the ransom or completely erase their device, losing all their photos and data unless they have a full backup elsewhere.”

Ruby on Rails

In January, it was announced that a critical vulnerability in the Ruby on Rails Framework could allow a remote attacker to execute code on the underlying Web server. Further adding to the problem, a Metasploit module was made available to scan for the vulnerability, making the ability to find a Web server to exploit a trivial matter.

“The exploit involved a flaw in the XML processor deserialization routine, which is used to create Ruby objects on the fly,” said Henderson. “RoR was patched to correct the flaw, but four months later it was discovered that an attacker or attackers was searching for and exploiting, unpatched Web servers in order to infect them with software.”

Java Remote code execution

In January, a zero-day exploit that was able to bypass Java’s sandbox and run arbitrary Java code was discovered. The vulnerability allowed a malicious applet to run any Java program, bypassing Java’s sandbox and granting full access to the vulnerable computer.

Attacks were discovered in the wild and the exploit was quickly integrated into many popular crimeware attack kits, such as BlackHole, Redkit and Nuclear Pack, giving purchasers of these kits the ability to take advantage of the exploit and install malware on computers. A Metasploit module was also created for the vulnerability, making the ability to find victims a simple point and click affair.

“The exploit involved a flaw in a JMX (Java Management Extensions) component that allowed the malicious applet to elevate its privileges and run any Java code it wished,” Henderson said.

Oracle was quick to release a patch for the flaw – but similar to other exploits integrated into crimeware kits, many new victims were found – and continue to be found – running unpatched versions of Java, allowing malware to be installed.

Acrobat/Acrobat Reader zero-day in the wild

In February, a PDF pretending to be a travel visa form from Turkey was detected circulating in the wild and took advantage of a previously unseen vulnerability in Adobe’s Reader software. The exploit worked with all recent versions of Adobe Reader (9.5.X, 10.1.X, and 11.0.X), and on most versions of Microsoft Windows, including 64-bit Windows 7 and most Mac OS X systems.

The exploit PDF was used by cybercriminals in order to install malware on their target’s computers.

Adobe released a patch for the flaws in Reader on February 20th, but cybercriminals continue to use repackaged versions of the exploits online in spear-phishing attacks. These exploits in Adobe’s Reader software continue to be actively exploited by cybercriminals as a malware delivery method, taking advantage of users who don’t expeditiously patch their computers.

CDorked attacks Apache

In late April, a new attack on the popular Apache Web server was discovered. Dubbed CDorked, the malware was able to compromise the Web server and redirect visitors of the compromised Web server to other servers that deliver malware using the BlackHole exploit kit. The attack may also have targeted the Lighttpd and Nginx Web server platforms.

CDorked shows many similarities to 2012’s DarkLeech attack on Apache servers, but is significantly stealthier and smarter than DarkLeech was: unlike DarkLeech, CDorked didn’t load additional malicious modules on the infected server; instead it maliciously modified the existing httpd binary.

CDorked was interesting in that it did not write any information to the Web server’s hard drive: everything was kept in memory and was accessed via obfuscated GET requests sent by the attackers to the compromised server. None of those GET requests were logged.

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