(CNN) -- Over the past week, two popular Internet messaging companies, SnapChat and Skype, were hacked. SnapChat's 4.6 million users' user names and cell phone numbers were posted online. A hacker group posted messages to Skype's official blog and social media accounts. These are just the latest in a long list of tech companies that fail to provide adequate protection of their users' personal data. Do companies that offer free services have an obligation to protect our communications? Yes, absolutely. SnapChat is an app for phones that allows people to send photos and short videos to friends and promises to delete them once viewed, Ã  la Mission Impossible.
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SnapChat's 4.6 million user names and cell phone numbers were posted online
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Chester Wisniewski: Safeguards exists and tech fixes are easy, so why the breach?
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He says Skype, SnapChat have obligation to make sure their services are secure
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Wisniewski: We must demand accountability from companies to protect our private data
@placeholder then blogged that it knew about the flaws, but was satisfied with the changes it implemented and didn't expect the service to be exploited.