Yahoo did not accept Microsoft’s bid by the Saturday deadline so now it’s up to the software giant to decide whether to pursue a hostile takeover or walk away from Yahoo altogether.A security think tank uncovers a vulnerability in Apple’s multimedia player that could allow a hacker to take complete control of Windows Vista or XP machines. Security vendors slam the Defcon virus contest that will award hackers for finding ways to beat antivirus software; the vendors claim it will only help the bad guys learn new tricks. Black Duck buys Koders for its code search engine and, in so doing, hopes to extend its reach into the open source developer community.And Interop stakes a new claim by adding a software show and security conference as the event branches out beyond enterprise networking. That said, Interop will offer datacenter products and 802.11n tools from the likes of AirMagnet and Citrix Systems. Related blog: Looking at Interop. Software Development