Yahoo! has patched a flaw in the open source Portable Network Graphics (PNG) image format that is utilized by its real-time communications product Yahoo! Messenger. Yahoo! spokesperson Terrell Karlsten told BetaNews, “Beginning today, we are notifying users who are currently running Windows versions 6.0 to install the security update. Upon logging into Yahoo! Messenger, users will be prompted with a message window that invites them to update their service.” Users may also download the new release separately.