New Java zero-day vulnerability has been spotted in the wild. We have seen this unpatched exploit being used in limited targeted attacks. Most of the recent Java run-time environments i.e., JRE 1.7x are vulnerable. In my lab environment, I was able to successfully exploit my test machine against latest version of FireFox with JRE version 1.7 update 6 installed.
Initial exploit is hosted on a domain named ok.XXX4.net. Currently this domain is resolving to an IP address in Taiwan. Attacker web site is fully functional at the time of writing this article i.e., on August 26, 2012.
A successful exploit attempt can result in a dropper (Dropper.MsPMs) getting installed on infected systems. The dropper executable is located on the same server.
Dropper.MsPMs further talks to its own CnC domain hello.icon.pk which is currently resolving to an IP address 22.214.171.124 located in Singapore.
It's just a matter of time that a POC will be released and other bad guys will get hold of this exploit as well. It will be interesting to see when Oracle plans for a patch, until then most of the Java users are at the mercy of this exploit. Our investigation is not over yet; more details will be shared on a periodic basis.
UPDATE: On August 30, Oracle released a patch for its Java plugin. Read more here.