Yahoo's IM update: A Trojan horse of surprises

Yahoo Messenger 8.1, when it was released Friday, automatically installed a Yahoo Mail icon in a user's system tray and changed the user's default mail settings to Yahoo Mail, said Karlsten.

Yahoo had alerted 73 million users worldwide (or all those using its IM service before November 2) to download the latest software version, which includes free or low-cost PC-to-PC calls among its chat features.

The company said the update increases stability and reliability, and improves security. The previous software contains a security flaw that could cause other applications like Microsoft's IE to crash, or prompt users to be involuntarily logged out, Karlsten said. The new version, she said, fixes that issue and bundles in new features like interoperability with Windows Live Messenger.

"The reason why we do a package, bundle everything together, is so people can get the latest version with the security updates and the great new features," Karlsten said.
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By default, the software also inserts the Yahoo Toolbar into the user's Web browser and changes the user's personalized home page and search settings to Yahoo.com. In the original download alert, people could choose to customize the installation under "options" and then uncheck these default settings. What users couldn't change, however, was that the software was adding a Yahoo Mail icon to the system tray and changed their default mail settings to Yahoo Mail.

Yahoo's Karlsten had said the engineering team was not aware of the Yahoo Mail issue and was actively working on a fix.

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