'Critical' Java Flaw Bugs Researchers

Sun patches some versions of Java - another patch, for consumers, is due this week

A serious Java vulnerability just patched by Sun Microsystems may still leave many Java users at risk, security experts say.

The stack buffer overflow bug in Java, the WebStart utility in the Java Runtime Environment, could be used by an attacker to insert a bot agent, rootkit, or backdoor malware on the victim's machine. A user would get infected either by clicking on a malicious link, or by unknowingly getting redirected to an infected Website. (The malware is contained in Java JNLP files.)

"Anyone with Java installed on Windows is automatically configured to load JNLP files without prompting," notes HD Moore, creator of Metasploit. "So it's pretty serious since it affects everyone [who has] Java installed."

Sun recently patched JRE 5 and the Java 6 developer version, but hasn't yet pushed a patch to consumer users' version 6, which it plans to do this week. The bug's danger at this point to users may be more a function of the patch process itself, according to security experts. "Most companies' patch management software is not configured to patch Java," says Marc Maiffret, eEye's CTO and chief hacking officer. "To make matters worse, Sun has such a horrible update process -- they released patches for this flaw a couple of weeks ago, and then more patches for a different version today. Which means if people were reverse-engineering the patch a few weeks ago, now they have a head start on the good guys."

A Sun spokesperson declined to comment on eEye's criticism of its patch process, but says the consumer version of the Java 6 patch is still being tested and should be available this week. Sun first issued a patch for the bug on June 28, for JRE 5, and then on July 2, it released a patch for Java 6 developers.

eEye, which discovered the bug over six months ago, has labeled the bug as "critical."

Still, neither Maiffret nor Metasploit's Moore were aware of any exploits in the wild based on this bug. eEye recommends that Java users immediately install the patches, which are available from Sun at http://java.sun.com/javase/downloads/index_jdk5.jsp for JRE 5 Update 12 and at http://java.sun.com/javase/downloads/index.jsp for JRE 6 Update 2.

— Kelly Jackson Higgins, Senior Editor, Dark Reading

About the Author(s)

Kelly Jackson Higgins, Editor-in-Chief, Dark Reading

Kelly Jackson Higgins is the Editor-in-Chief of Dark Reading. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise Magazine, Virginia Business magazine, and other major media properties. Jackson Higgins was recently selected as one of the Top 10 Cybersecurity Journalists in the US, and named as one of Folio's 2019 Top Women in Media. She began her career as a sports writer in the Washington, DC metropolitan area, and earned her BA at William & Mary. Follow her on Twitter @kjhiggins.

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