Java brews critical bug

Java bug can leave corporate systems open to attack

A bug in the Java Runtime Environment (JRE) can leave corporate systems open to attack if a user visits a site containing malicious code, security researchers have warned.

The bug affects Windows, Linux and Solaris, and Sun has released a patch.

The JRE includes the Java Virtual Machine and supporting executables and files, and contains safeguards that prevent applets from causing trouble on the wider system. The newly disclosed flaw allows applets to upgrade their privileges, effectively giving them free access to the rest of the system, Sun said in an advisory.

"For example, an applet may grant itself permissions to read and write local files or execute local applications with the privileges of the user running the untrusted applet," Sun said.

The specific bug is to do with the processing of GIF image components, according to the Zero Day Initiative (ZDI), a bounty-oriented program run by 3Com's TippingPoint, which bought rights to disclosure from an anonymous researcher.

"When the image width in an image block of a valid GIF file is set to 0, the Java runtime will allocate the specified size but subsequently copy all data to the under allocated memory chunk," ZDI said in its advisory. "The overflow results in the corruption of multiple pointers, at least one of which is later dereferenced and can therefore result in execution of arbitrary code."

ZDI originally informed Sun of the problem back in June, the organization said.

Secunia, a third-party security company based in Denmark, said the problem was one of the most serious to have affected Java in some time. Secunia said the bug was "highly critical".

The bug affects Java Development Kit (JDK) and JRE 5.0 Update 9 and prior, Java Software Development Kit (SDK) and JRE 1.4.2_12 and prior, and SDK and JRE 1.3.1_18 and prior.

Join the newsletter!


Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Matthew Broersma
Show Comments




Sony WH-1000XM4 Wireless Noise Cancelling Headphones

Learn more >


Back To Business Guide

Click for more ›

Brand Post

Shining a light on creativity

MSI has long pushed the boundaries of invention with its ever-evolving range of laptops but it has now pulled off a world first with the new MSI Creative 17.

Most Popular Reviews

Latest Articles


PCW Evaluation Team

Tom Pope

Dynabook Portégé X30L-G

Ultimately this laptop has achieved everything I would hope for in a laptop for work, while fitting that into a form factor and weight that is remarkable.

Tom Sellers


This smart laptop was enjoyable to use and great to work on – creating content was super simple.

Lolita Wang


It really doesn’t get more “gaming laptop” than this.

Jack Jeffries


As the Maserati or BMW of laptops, it would fit perfectly in the hands of a professional needing firepower under the hood, sophistication and class on the surface, and gaming prowess (sports mode if you will) in between.

Taylor Carr


The MSI PS63 is an amazing laptop and I would definitely consider buying one in the future.

Christopher Low

Brother RJ-4230B

This small mobile printer is exactly what I need for invoicing and other jobs such as sending fellow tradesman details or step-by-step instructions that I can easily print off from my phone or the Web.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?