Hackers Don't Need Wi-Fi to Steal Your Data

Your laptop or smartphone may be leaking electronic emissions that contain your password or other private data, even when it's not connected to the Internet, according to two groups of researchers.

The vulnerability could make it possible for a hacker to obtain information from your device just by sitting next to you at a coffee shop.

The researchers are tracing leaks of electromagnetic radiation that are byproducts of various electronic components of computer hardware, including computer processors and capacitors.

Some of the signals are created when you type at the keyboard and can be picked up with the right kind of electronic eavesdropping equipment.

In their recent study, the Georgia Tech researchers developed a way to measure the strength of the emissions and offer ways for hardware and software designers to plug those electronic holes.

So far, these kinds of leaks are not overly exploited by hackers.

"If you are comparing this to Internet attacks, it is less of a problem," said Alenka Zajic, assistant professor of electrical and computer engineering at the Georgia Institute of Technology.

"But they are very hard to detect. With any sort of Internet attack, you will find the attacker. With this one you just need to be close by and there's no way to know who took your data."

Zajic and her colleagues say they were able to pick up keystroke information from laptops using just an AM radio and a cellphone. "You could probably hide it under the desk," Zajic said. "It's just a matter of motivation."

These side-channel emissions can also be measured from hidden antennas in a briefcase, while acoustic emissions from the device's electronic capacitors, can be picked up by tiny microphones.

In her research, Zajic typed a password on one laptop that was not connected to the Internet. On the other side of a wall, a colleague using another disconnected laptop was able to intercept the side-channel signals produced and read the password as it was being typed.

Zajic said these small electronic emissions are tough to stop.

Zajic and which was presented recently at IEEE/ACM International Symposium on Microarchitecture in Cambridge, UK. Another team from Israel's Tel Aviv University has also been working on this problem.

The Georgia Tech researchers are also now studying smartphones, whose compact design and large differential between idle and in-use power may make them more vulnerable. So far, they have only looked at Android devices.

Because it's difficult to control these electronic signals without a jammer or protective metal cage, Zajic believes the solution may be in modifying software so it doesn't initiate a recognizable signal in the first place.

"If I can identify the part of the code that leaks the most," she said. "We can mask the emanations so you are protected."

So far, this kind of close-quarters hacking is probably only a threat to decision-makers, VIPs, politicians or celebrities that are in possession of valuable data, according to Miodrag Potkonjak, a computer scientist at UCLA. That might change as more people begin to use their smartphones to pay for consumer items, using near-field transmission to exchange data, such as Apple Pay.

"Soon it will be a big problem for everyone," said Potkonjak, who has studied encryption technologies and side-channel signals.

Data centers that store vast quantities of private information are also at risk, believes Simha Sethumadhavan, assistant professor of computer science at Columbia University.

"I don't think one can prevent side-channel attacks completely," he said via e-mail to Discovery News. "One solution is to add noise to frustrate the attacker, another solution is to make the secret signal output indistinguishable from non-secret operations -- this requires designers to think about the attack at run time, and yet another solution is to use algorithms that are leakage-resistant."

A computer vulnerability could make it possible for a hacker to obtain information from your device just by sitting next to you at a coffee shop.

Once relegated to the shadows of the digital underground, hacking has gone mainstream. Hardly a day goes by without the announcement of a major cybersecurity breach, sometimes conducted by groups, such as Anonymous and LulzSec, that are virtually becoming household names. Hacking has become so prevalent that it has even been allegedly used by major news organizations in the United Kingdom for news gathering. This year alone, there have been a number of high-profile attacks on major companies, such as Sony; international organizations, such as NATO; and even entire governments, as was the case most recently with Syria. Although the major players are becoming more familiar, to many, their methods are as opaque as they've always been. In this slideshow, explore some of the techniques used by hackers to exploit and overcome cybersecurity vulnerabilities.

Eavesdropping and Other Passive Attacks With a passive attack, computer systems and networks are monitored in order for a hacker to gain some information. One technique involves eavesdropping, where a hacker listens in on a network. The point isn't to cause damage to the computer system itself, but to harvest information as it's transmitted. This technique is also known as sniffing or snooping. Eavesdropping is not only a concern for computers, but also mobile devices as they become ubiquitous.

Viruses, Worms and Other Active Attacks Active attacks, such as viruses and trojans, are techniques where a hacker manipulates or deletes data to create the desired result. Computer viruses were first seen in the late 1980s just as home computers were growing more popular. As its name suggests, a virus is a piece of code attached to a seemingly innocuous program and passed between computers. Once inside a system, the virus spreads and can bring down a computer.  Like a virus, a Trojan horse is simply a computer program. As the name implies, a Trojan horse fools the user into thinking it's another kind of program, and once installed, releases a malicious code. Another cousin of the virus is the computer worm. Worms burrow into network security holes to pass and install malicious code from user to user. One of the most severe cyber-attacks of all time was through the accidental use of a worm by a graduate student in 1988, who was looking to determine the size of the Internet. Software used for a variety of functions from disrupting a system to gaining access to a network is often called malware. Spyware serves to collect information on users and may or may not be malicious. Not all spyware is malware and vice versa. There are also more niche subcategories of malware, such as ransomware, a term used for an attack meant to scare the user into paying what is essentially a form of blackmail, or scareware, a product falsely sold under the premise that it will protect your computer from outside threats.

Denial of Service A denial of service attack is a technique intended to impede normal operations of a website or network.  The basic idea is to overrun a computer or server with requests from outside a network to overwhelm the system's available resources. By flooding the intended target with requests, hackers incapacitate the site.  These attacks often employ botnets, also known as zombie computers, which are systems that are taken over, sometimes unknowingly though occasionally voluntarily, by a hacker. This technique was most notably employed by the hacking group known as Anonymous against various websites, including Mastercard, Visa, Paypal and others, in the wake of the controversy surrounding the online whistleblower Wikileaks.

Going In The Back Door Earlier this year, hackers shut down Sony's PlayStation Network and stole the personal information, including some credit card data, from nearly 100 millions users. According to a letter by Sony following a Congressional inquiry into the matter, the company asserted that the heist was the result of two groups of hackers: the first launched a denial of service attack while the second stole the data. Before this series of attacks took place, however, Sony itself was accused of slipping malicious code -- a rootkit -- into one of its firmware updates for the PlayStation 3. A rootkit, also known as a back door, is software that gives a hacker access to a computer or network, often without an administrator's knowledge. Gaming security experts, however, dismissed the rumors as false.

Phishing and Sidejacking Behind almost all secure data both online and off is a username and password. If a hacker can gain user information and crack a password, that attacker can access a network and create, modify or delete data maliciously. Different techniques, however, are used to steal a user's password. One of the most popular methods is known as phishing.  It starts when a hacker sends an electronic communication to an unsuspecting user under the illusion that the message is from a trusted institution. The user is duped into supplying his information, which may not only include a username and password but also a social security number and bank account information. Another method, known as sidejacking, session IDs, which can be unencrypted data in a URL or cookie, to gain access to an account. Other automated attacks simply guess passwords using predetermined dictionaries and often exploits systems without lockout policies for successive login failures.

Keylogging Keylogging is a technique that could be used for password cracking, but goes a step further.  It allows hackers to monitor every stroke of the key entered by a user, which could include other information besides passwords, such as social security numbers, credit card data and much more.

Spoofing With spoofing attacks, hackers pretend to be a user designated to access a particular system or network by mimicking that person's IP address. Once a hacker is inside the system, that attacker can steal or delete data, or access other resources within a particular network.