YIM users running version 11.x of the instant messaging client are not vulnerable to the status-change mechanism anymore. Bitdefender discovered the flaw last Friday as part of a forensic investigation on a customers machine. If you are running a vulnerable version of the product, you should know that you dont have to download and install anything, as the fix has been applied server-side. The fix has now been applied to all versions of the YIM client.”]
Source: https://www.bitdefender.com/blog/hotforsecurity/yahoo-closes-zero-day-yim-hole/