The hackers who maintain Blackhole and Nuclear Pack — competing crimeware products that are made to be stitched into hacked sites and use browser flaws to foist malware — say they’ve added a brand new exploit that attacks a previously unknown and currently unpatched security hole in Java.
The curator of Blackhole, a miscreant who uses the nickname “Paunch,” announced yesterday on several Underweb forums that the Java zero-day was a “New Year’s Gift,” to customers who use his exploit kit. Paunch bragged that his was the first to include the powerful offensive weapon, but shortly afterwards the same announcement was made by the maker and seller of Nuclear Pack.
According to both crimeware authors, the vulnerability exists in all versions of Java 7, including the latest — Java 7 Update 10. This information could not be immediately verified, but if you have Java installed, it would be a very good idea to unplug Java from your browser, or uninstall this program entirely if you don’t need it. I will update this post as more information becomes available.
Update, 8:47 a.m. ET: Alienvault Labs say they have reproduced and verified the claims of a new Java zero-day that exploits a vulnerability (CVE-2013-0422) in fully-patched versions of Java 7.
Update, 11:46 a.m. ET: As several readers have noted, Java 7 Update 10 ships with a feature that makes it far simpler to unplug Java from the browser than in previous. Oracle’s instructions for using that feature are here, and the folks at DHS’s U.S.-CERT are now recommending this method as well.