Hot Off the Web: New Java 0-Day Vulnerability
The latest buzz on security and vulnerability these past few days revolves around Java, a software development platform originally created by Sun Microsystems and now owned by Oracle. Websites often run Java programs in them, normally as applets (.jar), in order to “provide interactive features to web applications that cannot be provided by HTML alone”. Initial reports reveal that the exploit used to take advantage of the vulnerability found in Java 7—version 1.7, updates 0 to 6—is an applet called applet.jar (Note that names of malicious files can change in the future).
Our friends at FireEye first uncovered the new 0-day Java Runtime Environment (JRE) vulnerability being exploited in the wild. It is leveraged by online criminals to perform targeted attacks, regardless of the Internet browser used or how updated it is. “The number of these attacks has been relatively low, but it is likely to increase due to the fact that this is a fast and reliable exploit that can be used in drive-by attacks and all kinds of links in emails.” said Andre’ M. DiMino and Mila Parkour of DeepEnd Research in their blog entry. An official patch from Oracle is yet to be released; however, our friends at DeepEnd are distributing a temporary fix, courtesy of Michael Schier, to system administrators only and by request. The said patch allows the execution of the exploit but stops the payload.
Once the vulnerability is successfully exploited, a binary is dropped on the compromised system. Based on initial reports, the binary is hi.exe (MD5: 4a55bf1448262bf71707eef7fc168f7d), whichGFI VIPRE Antivirus already detects as Trojan.Win32.Generic!BT.
Although earlier releases of Java do not have the said JRE vulnerability, security researchers advised against downgrading to versions 1.6 and below as flaws inherent to those versions can still affect users. Instead, users are advised to disable Java on their browser for the time being until an official patch is made available. It is expected in October based on their triannual Java patch release schedule.