Yahoo Widgets users were warned last week that the web-based, gadget-like apps feature a critical flaw allowing hackers can use to hijack Windows PCs.
A bug in an ActiveX control that ships with Yahoo Widgets can be exploited to create a buffer overflow, and after that, introduce rogue code to the compromised computer. The most likely attack scenario, said Yahoo, would find attackers feeding users' links to malicious websites.
Yahoo issued an update to Widgets' engine earlier this week, but it was just today that Danish vulnerability tracker Secunia, which reported the bug to Yahoo, announced the flaw. Secunia said the problem was 'extremely critical', the second-highest threat rating in its five-step scoring system.
Users have reported, however, that although they have the Widgets' automatic update mechanism turned on, they've not received notice of the patch. Yahoo acknowledged this in a security advisory posted on the Widgets site. "Over the next several weeks, users worldwide will be prompted to update to a new version of Yahoo Widgets," the alert read.
Only the Windows version of Yahoo Widgets is at risk; the Mac OS X edition does not need to be updated.
Users can download Yahoo Widgets 4.0.5 rather than wait for the update notification, Yahoo said.
Yahoo Widgets, formerly known as Konfabulator before Yahoo's acquisition of the software in 2005, competes with Windows Vista's Sidebar and with the Mac OS X's Dashboard. The number of gadgets/widgets for each of those rivals, however, falls far short of the 4,000 or available for Yahoo's engine.