Amazon.com has required an undisclosed number of customers to reset passwords to their online accounts after the company said some passwords "may have been improperly stored" on devices.
Facebook on Monday followed in Google's footsteps and began warning users when it appears they are targeted by state-sponsored cyber attacks.
Apple on Friday rid its App Store of some applications that it said could snoop on people's data and posed a security threat.
T-Mobile's chief executive has expressed outrage over a breach at a credit monitoring service that exposed private data from 15 million customers of the mobile carrier.
Researchers at the University of Birmingham have developed a technique to allow people to cast their election vote online - even if their home computers are suspected of being infected with viruses.
Americans have been stepping up efforts to keep their data private since the revelations about vast US government surveillance programs, a survey showed Monday.
Online payments group PayPal announced Tuesday it was acquiring Israeli cybersecurity firm CyActive and establishing a new security hub in Israel.
The boom in smartphones among often careless users has made happy hunting for hackers, whose virus attacks and hijacking of unprotected mobiles are multiplying, experts warn.
Marriage therapist Valerie Goss turned on her computer one day and found that all of her data was being held hostage.
It would be another powerful tool in the arsenal of US and British spy services: encryption keys for a large share of the SIM cards used for mobile phones.