A Yahoo sign at the company's headquarters in Sunnyvale, Calif. The company has announced a hacking of user accounts that happened in 2013, but it says payment card information was not accessed.
Marcio Jose Sanchez/AP
The Nest thermostat is an Internet-connected device. Security technologist Bruce Schneier says that while Internet-enabled devices have immense promise, they are vulnerable to hacking.
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People walk past a TV screen showing a poster of Sony Picture's "The Interview" in a news report, at the Seoul Railway Station in Seoul, South Korea. The FBI says North Korea hacked into Sony Pictures computer systems as retribution for the film.
Dartmouth College researcher Timothy Pierson holds a prototype of Wanda, which is designed to establish secure wireless connections between devices that generate data.
Eli Burakian/Dartmouth College
A pedestrian walks by an Apple store in New York City on Feb. 23. Protesters demonstrated against the FBI's efforts to require the company to make it easier to unlock the encrypted iPhone used by Syed Rizwan Farook.
Secretary of Defense Ash Carter (left) says the Pentagon's new hacker program will strengthen America's digital defenses. Carter is seen here with the chairman of the Joint Chiefs of Staff, Gen. Joseph Dunford.
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Authorities say several publicly traded companies, including Clorox, Caterpillar and Viacom, had press releases stolen and used to implement an insider-trading scheme.
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