Most of 55,000 HVAC systems connected to the Internet have flaws that can be easily exploited by hackers, security firm says. Such a flaw was used by hackers in the Target breach, Qualys says. The Sochi Olympics system doesn’t even require a password, so if you know the IP address, you’re in, company says. HVac systems connect to networks at various retail companies, government buildings and even hospitals, according to the security firm. The Target breach shows why companies need to implement measures for controlling what third-parties can do on their networks.”]