Windows 7: Java Exploits

The recent Java JRE patch bundle released by Oracle contained a long list of security fixes, several of which for vulnerabilities that allow drive-by exploits. And since Java is present on pretty much every Windows PC, and people don't seem to do their Java updates quite as diligently as their Windows patches, there are A LOT of vulnerable PCs out there. Microsoft reported on this a month ago, and called it an "unprecedented wave of Java exploiting".

It doesn't look like the situation has improved since, and the bad guys are taking advantage. Not surprisingly, the FAQ document on "Virus found in my Java Cache Directory" is ranked third most popular of all the issues listed on Java Help Center. The two issues ranked ahead of it are also security concerns.. not a pretty picture for Oracle or Java, I'd say.

Let's take a look at one of the popular exploits that are making the rounds, the "bpac" family. The exploit used is for CVE-2010-0840 (Hashmap), already covered by the Java patch bundle in July, but apparently still successful enough to be used. I guess the bad guys won't start "burning" their newest Java exploits while the old set is still going strong.

The infection usually happens as follows:
(1) User surfs to website that has been injected with the exploit
(2) Exploit pack triggers - it comes as an obfuscated JavaScript that downloads an Applet and a PDF
(3) The applet contains an exploit, here for CVE-2010-0840
(4) The applet is invoked with a parameter that tells it where to find the EXE
(5) If the exploit is successful, the EXE is downloaded and run

The EXEs pack quite a punch - one recent sample submitted contained no less than 66 individual other malicious EXEs. Yes, a user would be bound to notice this deluge of badness, but he still wouldn't stand a chance to ever clean ALL of this crud off the system again.