"In the past year or so the bad guys started paying much more attention to Java exploits," said Trustwave SpiderLabs security researcher Arseny Levin earlier this year in a blog post. "Java is a very appealing target, since it can be found on your home desktop, on your mobile, and even on many embedded devices." Furthermore, he noted that some vulnerabilities can be exploited via Java Virtual Machine shell bytecode, "meaning exploitation will be successful regardless of the operating system." The Apple OS X Flashback malware was one example of such an attack.
According to a BlackHole control panel screenshot published by Seculert, the Java array vulnerability found earlier this year--and targeted by Flashback--was successfully exploited by the exploit kit between 76% and 97% of the time.
5. Java Exploits Wildly Successful
Now, the BlackHole developer's rapid response has paid off for his crimeware customers. "We were able to count tens of thousands of new infected machines due to the Java 0-day, since the exploit was added to the BlackHole exploit kit," according to a blog post from the company. "Usually, a good exploit kit like BlackHole has a success rate of around 10% for infecting machines visiting the servers. In the new version of BlackHole infection servers, we have seen up to a 25% percent success rate," it noted, and said 99% of those successful exploits were thanks to using Java vulnerabilities.
Small wonder that Sean Sullivan, security advisor at F-Secure Labs, has dubbed the Java runtime environment (JRE) as a "perpetual vulnerability machine."
6. Malware May Be Targeting Mac Users
A variant of the Tsunami malware that can target both OS X and Linux systems may already be using the new Java vulnerabilities to infect systems. "This method of infection has not yet been confirmed, but as this OS X malware connects out to the same IP address as the Windows backdoors known to be dropped by [the Java vulnerability], it seems they are at least related incidents," said Lysa Myers, a "virus hunter" at Mac security software firm Intego, in a Wednesday blog post.
"At the time of writing, the JAR file that was purported to be dropping this Trojan has been replaced with a bit of threatening text. It seems like maybe someone knows they've been discovered?" she said.
One piece of good news for Mac users, however, is that only Java 6 is included by Apple in OS X. While Mac users can upgrade to Java 7, they would have had to have done so manually.