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By Cracking Cellphone Code, Nsa Has Capacity For Decoding Private Conversations

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A cellphone user under surveillance.

The U.S. National Security Agency can crack the encryption technology used on most cellphones worldwide.

Credit: Francisco Seco/AP

The U.S. National Security Agency is able to crack the A5/1 encryption technology used on most cellphones worldwide, giving the agency the ability to access the majority of private calls and texts, according to an internal document released by The Washington Post.

The NSA's global signal collection operation means that its access to private cellphone communications is far broader than military and law enforcement agencies' ability to hack into individual cellphones. Although U.S. law requires NSA to obtain a court order before gathering the content of conversations between Americans, experts warn that if the agency can easily crack encrypted cellphone conversations, other nations' intelligence services can likely do the same. A5/1 encryption's flaws have been noted by security experts, but most providers have not upgraded to newer systems that are more secure. NSA "can process encrypted A5/1" even without an encryption key, according to the internal document, although the scope of the agency's collection and its use of decryption tools remains unclear.

Experts say A5/1 has been repeatedly cracked by researchers in demonstration projects for more than a decade. The encryption technology "was designed 30 years ago, and you wouldn't expect a 30-year-old car to have the latest safety mechanisms," says University of California, Berkeley professor David Wagner.

From The Washington Post
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Abstracts Copyright © 2013 Information Inc., Bethesda, Maryland, USA


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