Investigation Report: Cell-Phone Viruses Work

How Cell-phone Viruses Work

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Future cell-phone viruses may be as debilitating as computer viruses.

The first known cell-phone virus appeared in 2004 and didn't get very far. Cabir.A infected only a small number of Bluetooth-enabled phones and carried out no malicious action -- a group of malware developers created Cabir to prove it could be done. Their next step was to send it to anti-virus researchers, who began the process of developing a solution to a problem that promises to get a lot worse.
­ Cell-phone viruses are at the threshold of their effectiveness. At present, they can't spread very far and they don't do much damage, but the future might see cell-phone bugs that are as debilitating as computer viruses. In this article, we'll talk about how cell-phone viruses spread, what they can do and how you can protect your phone from current and future threats.

Cell-phone Virus Basics:

A cell-phone virus is basically the same thing as a computer virus -- an unwanted executable file that "infects" a device and then copies itself to other devices. But whereas a computer virus or worm spreads through e-mail attachments and Internet downloads, a cell-phone virus or worm spreads via Internet downloads, MMS (multimedia messaging service) attachments and Bluetooth transfers. The most common type of cell-phone infection right now occurs when a cell phone downloads an infected file from a PC or the Internet, but phone-to-phone viruses are on the rise.

Current phone-to-phone viruses almost exclusively infect phones running the Symbian operating system. The large number of proprietary operating systems in the cell-phone world is one of the obstacles to mass infection. Cell-phone-virus writers have no Windows-level marketshare to target, so any virus will only affect a small percentage of phones.

Infected files usually show up disguised as applications like games, security patches, add-on functionalities and, of course, pornography and free stuff. Infected text messages sometimes steal the subject line from a message you've received from a friend, which of course increases the likelihood of your opening it -- but opening the message isn't enough to get infected. You have to choose to open the message attachment and agree to install the program, which is another obstacle to mass infection: To date, no reported phone-to-phone virus auto-installs. The installation obstacles and the methods of spreading limit the amount of damage the current generation of cell-phone virus can do.

That Thing with Paris Hilton's Phone:

Remember when someone got his hands on Paris Hilton's star-studded contact list? It was not the result of a virus, and nobody hacked into Hilton's phone. Mobile phone servers hold on to certain types of information, such as contact lists (in case the user's phone locks up) and recent calls (for billing purposes). The enterprising hacker got into T-mobile's servers and stole the information from there.

How They Spread:

Cell phones can catch viruses when they download an infected file.

 

Phones that can only make and receive calls are not at risk. Only smartphones with a Bluetooth connection and data capabilities can receive a cell-phone virus. These viruses spread primarily in three ways:

• Internet downloads - The virus spreads the same way a traditional computer virus does. The user downloads an infected file to the phone by way of a PC or the phone's own Internet connection. This may include file-sharing downloads, applications available from add-on sites (such as ringtones or games) and false security patches posted on the Symbian Web site.
• Bluetooth wireless connection - The virus spreads between phones by way of their Bluetooth connection. The user receives a virus via Bluetooth when the phone is in discoverable mode, meaning it can be seen by other Bluetooth-enabled phones. In this case, the virus spreads like an airborne illness. According to TechnologyReview.com, cell-phone-virus researchers at F-Secure's U.S. lab now conduct their studies in a bomb shelter so their research topics don't end up spreading to every Bluetooth-enabled phone in the vicinity.
• Multimedia Messaging Service - The virus is an attachment to an MMS text message. As with computer viruses that arrive as e-mail attachments, the user must choose to open the attachment and then install it in order for the virus to infect the phone. Typically, a virus that spreads via MMS gets into the phone's contact list and sends itself to every phone number stored there.

In all of these transfer methods, the user has to agree at least once (and usually twice) to run the infected file. But cell-phone-virus writers get you to open and install their product the same way computer-virus writers do: The virus is typically disguised as a game, security patch or other desirable application.

The Commwarrior virus arrived on the scene in January 2005 and is the first cell-phone virus to effectively spread through an entire company via Bluetooth (see ComputerWorld.com: Phone virus spreads through Scandinavian company). It replicates by way of both Bluetooth and MMS. Once you receive and install the virus, it immediately starts looking for other Bluetooth phones in the vicinity to infect. At the same time, the virus sends infected MMS messages to every phone number in your address list. Commwarrior is probably one of the more effective viruses to date because it uses two methods to replicate itself.
So what does a virus like this do once it infects your phone?

Quiz Corner

How much you know about cell phones and what they do? Test your knowledge with our Cell Phone Quiz!

The Damage Done:

The first known cell-phone virus, Cabir, is entirely innocuous. All it does is sit in the phone and try to spread itself. Other cell-phone viruses, however, are not as harmless.

A virus might access and/or delete all of the contact information and calendar entries in your phone. It might send an infected MMS message to every number in your phone book -- and MMS messages typically cost money to send, so you're actually paying to send a virus to all of your friends, family members and business associates. On the worst-case-scenario end, it might delete or lock up certain phone applications or crash your phone completely so it's useless. Some reported viruses and their vital statistics are listed below.
As you can see from the above descriptions, cell-phone viruses have gotten a lot more harmful since the Cabir worm landed in the hands of researchers in 2004. But on the bright side, there are some steps you can take to protect your phone.

Cell-phone Viruses:

Cabir.A
First reported: June 2004
Attacks: Symbian Series 60 phones
Spreads via: Bluetooth
Harm: none
More information (including disinfection): http://www.f-secure.com/v-descs/cabir.shtml

Skulls.A
First reported: November 2004
Attacks: various Symbian phones
Spreads via: Internet download
Harm: disables all phone functions except sending/receiving calls
More information (including disinfection): http://www.f-secure.com/v-descs/skulls.shtml

Commwarrior.A
First reported: January 2005
Attacks: Symbian Series 60 phones
Spreads via: Bluetooth and MMS
Harm: sends out expensive MMS messages to everyone in phonebook (in course of MMS replication)
More information (including disinfection): http://www.f-secure.com/v-descs/commwarrior.shtml

Locknut.B
First reported: March 2005
Attacks: Symbian Series 60 phones
Spreads via: Internet download (disguised as patch for Symbian Series 60 phones)
Harm: crashes system ROM; disables all phone functions; inserts other (inactive) malware into phone
More information (including disinfection): http://www.f-secure.com/v-descs/locknut_b.shtml

Fontal.A
First reported: April 2005
Attacks: Symbian Series 60 phones
Spreads via: Internet download
Harm: locks up phone in startup mode; disables phone entirely
More information (including disinfection): http://www.f-secure.com/v-descs/fontal_a.shtml

Protecting Your Phone:

The best way to protect yourself from cell-phone viruses is the same way you protect yourself from computer viruses: Never open anything if you don't know what it is, haven't requested it or have any suspicions whatsoever that it's not what it claims to be. That said, even the most cautious person can still end up with an infected phone. Here are some steps you can take to decrease your chances of installing a virus:

• Turn off Bluetooth discoverable mode. Set your phone to "hidden" so other phones can't detect it and send it the virus. You can do this on the Bluetooth options screen.
• Check security updates to learn about filenames you should keep an eye out for. It's not fool-proof -- the Commwarrior program generates random names for the infected files it sends out, so users can't be warned not to open specific filenames -- but many viruses can be easily identified by the filenames they carry. Security sites with detailed virus information include: F-Secure, McAfee and  Symantec.
• Some of these sites will send you e-mail updates with new virus information as it gets posted.
• Install some type of security software on your phone. Numerous companies are developing security software for cell phones, some for free download, some for user purchase and some intended for cell-phone service providers. The software may simply detect and then remove the virus once it's received and installed, or it may protect your phone from getting certain viruses in the first place. Symbian has developed an anti-virus version of its operating system that only allows the phone's Bluetooth connection to accept secure files.

Although some in the cell-phone industry think the potential problem is overstated, most experts agree that cell-phone viruses are on the brink of their destructive power. Installing a "security patch" that ends up turning your phone into a useless piece of plastic is definitely something to be concerned about, but it could still get worse. Future possibilities include viruses that bug phones -- so someone can see every number you call and listen to your conversations -- and viruses that steal financial information, which would be a serious issue if smartphones end up being used as payment devices (see Bankrate.com: Paying by cell phone on the way).
 Ultimately, more connectivity means more exposure to viruses and faster spreading of infection. As smartphones become more common and more complex, so will the viruses that target them.

Investigation Report: Project Biometrics

How Biometrics Works !

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Vein scanning is one form of biometric identification.

Imagine you're James Bond, and you have to get into a secret laboratory to disarm a deadly biological weapon and save the world. But first, you have to get past the security system. It requires more than just a key or a password -- you need to have the villain's irises, his voice and the shape of his hand to get inside.
You might also encounter this scenario, minus the deadly biological weapon, during an average day on the job. Airports, hospitals, hotels, grocery stores and even Disney theme parks increasingly use biometrics -- technology that identifies you based on your physical or behavioral traits -- for added security.

In this article, you'll learn about biometric systems that use handwriting, hand geometry, voiceprints, iris structure and vein structure. You'll also learn why more businesses and governments use the technology and whether Q's fake contact lenses, recorded voice and silicone hand could really get James Bond into the lab (and let him save the world).

You take basic security precautions every day -- you use a key to get into your house and log on to your computer with a username and password. You've probably also experienced the panic that comes with misplaced keys and forgotten passwords. It isn't just that you can't get what you need -- if you lose your keys or jot your password on a piece of paper, someone else can find them and use them as though they were you.

Instead of using something you have (like a key) or something you know (like a password), biometrics uses who you are to identify you. Biometrics can use physical characteristics, like your face, fingerprints, irises or veins, or behavioral characteristics like your voice, handwriting or typing rhythm. Unlike keys and passwords, your personal traits are extremely difficult to lose or forget. They can also be very difficult to copy. For this reason, many people consider them to be safer and more secure than keys or passwords.

Biometrics uses unique features, like the iris of your eye, to identify you.

Biometric systems can seem complicated, but they all use the same three steps:

• Enrollment: The first time you use a biometric system, it records basic information about you, like your name or an identification number. It then captures an image or recording of your specific trait.
• Storage: Contrary to what you may see in movies, most systems don't store the complete image or recording. They instead analyze your trait and translate it into a code or graph. Some systems also record this data onto a smart card that you carry with you.
• Comparison: The next time you use the system, it compares the trait you present to the information on file. Then, it either accepts or rejects that you are who you claim to be.

This laptop features a fingerprint scanner, bringing biometric security to the home.

Systems also use the same three components:

• A sensor that detects the characteristic being used for identification
• A computer that reads and stores the information
• Software that analyzes the characteristic, translates it into a graph or code and performs the actual comparisons

Biometric security systems, like the fingerprint scanner available on the IBM ThinkPad T43 (right), is becoming more common for home use. You can read other HowStuffWorks articles to learn about face recognition and fingerprint scanning.

Next, we'll examine how biometrics provides security using other traits, starting with handwriting.

Handwriting:

This Tablet PC has a signature verification system.

At first glance, using handwriting to identify people might not seem like a good idea. After all, many people can learn to copy other people's handwriting with a little time and practice. It seems like it would be easy to get a copy of someone's signature or the required password and learn to forge it.

But biometric systems don't just look at how you shape each letter; they analyze the act of writing. They examine the pressure you use and the speed and rhythm with which you write. They also record the sequence in which you form letters, like whether you add dots and crosses as you go or after you finish the word.

Unlike the simple shapes of the letters, these traits are very difficult to forge. Even if someone else got a copy of your signature and traced it, the system probably wouldn't accept their forgery.
A handwriting recognition system's sensors can include a touch-sensitive writing surface or a pen that contains sensors that detect angle, pressure and direction. The software translates the handwriting into a graph and recognizes the small changes in a person's handwriting from day to day and over time.

Hand and Finger Geometry:

A hand geometry scanner

 

People's hands and fingers are unique -- but not as unique as other traits, like fingerprints or irises. That's why businesses and schools, rather than high-security facilities, typically use hand and finger geometry readers to authenticate users, not to identify them. Disney theme parks, for example, use finger geometry readers to grant ticket holders admittance to different parts of the park. Some businesses use hand geometry readers in place of timecards.

Systems that measure hand and finger geometry use a digital camera and light. To use one, you simply place your hand on a flat surface, aligning your fingers against several pegs to ensure an accurate reading. Then, a camera takes one or more pictures of your hand and the shadow it casts. It uses this information to determine the length, width, thickness and curvature of your hand or fingers. It translates that information into a numerical template.

Hand and finger geometry systems have a few strengths and weaknesses. Since hands and fingers are less distinctive than fingerprints or irises, some people are less likely to feel that the system invades their privacy. However, many people's hands change over time due to injury, changes in weight or arthritis. Some systems update the data to reflect minor changes from day to day.

For higher-security applications, biometric systems use more unique characteristics, like voices. We'll look at those next.

Voiceprints:

Speaker recognition systems use spectrograms to represent human voices.

 

Your voice is unique because of the shape of your vocal cavities and the way you move your mouth when you speak. To enroll in a voiceprint system, you either say the exact words or phrases that it requires, or you give an extended sample of your speech so that the computer can identify you no matter which words you say.

When people think of voiceprints, they often think of the wave pattern they would see on an oscilloscope. But the data used in a voiceprint is a sound spectrogram, not a wave form. A spectrogram is basically a graph that shows a sound's frequency on the vertical axis and time on the horizontal axis. Different speech sounds create different shapes within the graph. Spectrograms also use colors or shades of grey to represent the acoustical qualities of sound. This tutorial has a lot more information on spectrograms and how to read them.

Some companies use voiceprint recognition so that people can gain access to information or give authorization without being physically present. Instead of stepping up to an iris scanner or hand geometry reader, someone can give authorization by making a phone call. Unfortunately, people can bypass some systems, particularly those that work by phone, with a simple recording of an authorized person's password. That's why some systems use several randomly-chosen voice passwords or use general voiceprints instead of prints for specific words. Others use technology that detects the artifacts created in recording and playback.

Other systems are more difficult to bypass. We'll look at some of those next.

Layered vs. Multimodal:

For some security systems, one method of identification is not enough. Layered systems combine a biometric method with a keycard or PIN. Multimodal systems combine multiple biometric methods, like an iris scanner and a voiceprint system.

Iris Scanning:

 

Eye anatomy 

Iris scanning can seem very futuristic, but at the heart of the system is a simple CCD digital camera. It uses both visible and near-infrared light to take a clear, high-contrast picture of a person's iris. With near-infrared light, a person's pupil is very black, making it easy for the computer to isolate the pupil and iris.
When you look into an iris scanner, either the camera focuses automatically or you use a mirror or audible feedback from the system to make sure that you are positioned correctly. Usually, your eye is 3 to 10 inches from the camera. When the camera takes a picture, the computer locates:

• The center of the pupil
• The edge of the pupil
• The edge of the iris
• The eyelids and eyelashes
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It then analyzes the patterns in the iris and translates them into a code.

An iris scanner

Iris scanners are becoming more common in high-security applications because people's eyes are so unique (the chance of mistaking one iris code for another is 1 in 10 to the 78th power [ref]. They also allow more than 200 points of reference for comparison, as opposed to 60 or 70 points in fingerprints.

The iris is a visible but protected structure, and it does not usually change over time, making it ideal for biometric identification. Most of the time, people's eyes also remain unchanged after eye surgery, and blind people can use iris scanners as long as their eyes have irises. Eyeglasses and contact lenses typically do not interfere or cause inaccurate readings.

Vein Geometry:

Vein scanners use near-infrared light to reveal the patterns in a person's veins. 

As with irises and fingerprints, a person's veins are completely unique. Twins don't have identical veins, and a person's veins differ between their left and right sides. Many veins are not visible through the skin, making them extremely difficult to counterfeit or tamper with. Their shape also changes very little as a person ages.
To use a vein recognition system, you simply place your finger, wrist, palm or the back of your hand on or near the scanner. A camera takes a digital picture using near-infrared light. The hemoglobin in your blood absorbs the light, so veins appear black in the picture. As with all the other biometric types, the software creates a reference template based on the shape and location of the vein structure.

Scanners that analyze vein geometry are completely different from vein scanning tests that happen in hospitals. Vein scans for medical purposes usually use radioactive particles. Biometric security scans, however, just use light that is similar to the light that comes from a remote control. NASA has lots more information on taking pictures with infrared light.
Next, we'll look at some of the concerns about biometric methods.

Privacy and Other Concerns:

Some people object to biometrics for cultural or religious reasons. Others imagine a world in which cameras identify and track them as they walk down the street, following their activities and buying patterns without their consent. They wonder whether companies will sell biometric data the way they sell e-mail addresses and phone numbers. People may also wonder whether a huge database will exist somewhere that contains vital information about everyone in the world, and whether that information would be safe there.

At this point, however, biometric systems don't have the capability to store and catalog information about everyone in the world. Most store a minimal amount of information about a relatively small number of users. They don't generally store a recording or real-life representation of a person's traits -- they convert the data into a code. Most systems also work in only in the one specific place where they're located, like an office building or hospital. The information in one system isn't necessarily compatible with others, although several organizations are trying to standardize biometric data.

In addition to the potential for invasions of privacy, critics raise several concerns about biometrics, such as:

• Over reliance: The perception that biometric systems are foolproof might lead people to forget about daily, common-sense security practices and to protect the system's data.
• Accessibility: Some systems can't be adapted for certain populations, like elderly people or people with disabilities.
• Interoperability: In emergency situations, agencies using different systems may need to share data, and delays can result if the systems can't communicate with each other.

Investigation Report: Bad Affect Of Biometrics

How will biometrics affect our privacy?

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Fingerprint scanners are a popular type of biometric system.

We've all seen movies in which a character has a retinal scan to prove his or her identity before walking into a top-secret installation. That's an example of a biometric system. In general, biometrics is a collection of measures of human physiology and behavior. A biometric system could scan a person's fingerprint or analyze the way he or she types on a keyboard. The purpose of most biometric systems is to authenticate a person's claimed identity.

Biometrics tend to be more convenient than other methods of identity authentication. You might forget your ID at home when you head out the door, but you'll still be able to use biometric devices. Imagine verifying your identity while at the store by swiping your finger across a sensor.
                                                                                                                                                                        
But along with convenience and security comes a concern for privacy. For biometrics to work, there needs to be a database containing the relevant information for each individual authorized by the system. For example, at that top-secret installation, every employee's biometric signature would have to be recorded so that the scanners could verify each person's identity.

This might not present much of a problem on its own. If the only data the system stores relates to the actual biometric measurements, privacy violations are at a minimum. But by their very nature, biometric systems collect more information than just the users' fingerprints, retinal patterns or other biometric data. At a basic level, most systems will record when and where a person is at the time of a scan.

I Recognize That Face:

 

Biometric systems with cameras may use facial recognition software or study the way you move to identify you.

You might think of fingerprint or retinal scanners when you hear the word biometrics, but the term has a broader definition. Facial recognition technology falls into the biometric category. There are already several cameras on the market that can detect faces. A few are able to recognize and remember a group of faces. You just take a picture of a friend, tag the photo and the camera will automatically tag any future photos of that friend. It's both cool and creepy.

Imagine using this technology in public places to identify the people passing through. For example, a major city might install cameras at high-traffic areas to scan for terrorists or identify criminals. While the motivation for using that technology might be pure, it creates difficult privacy issues. The city would have a record of everyone who passed through that neighborhood. The technology treats everyone as a suspect as if it's only a matter of time before each of us commits a crime.

And what happens if the technology makes a mistake and misidentifies someone? Weather conditions, clothing, hairstyles and even the cleanliness of the lens could affect the ability of the camera to identify people. Critics might ask: Why install a system that's unreliable?

What happens if a person suffers an illness or injury that changes his or her appearance? Such a change could present problems with biometrics. Adjusting the biometric system to accommodate the change could also result in a violation of the user's privacy. The system administrator now knows more details about the user.

A society with pervasive biometric systems would make anonymity a virtual impossibility. Should that society become oppressive or otherwise abusive to the population, the citizens would have few opportunities to react without revealing their own identities.

Groups like the Biometrics Institute are aware of privacy concerns and strive to create processes to limit the chance for biometric applications to violate a person's privacy. Other groups advocate that companies, governments and other organizations conduct a privacy assessment before installing a biometric system. With vigilance and caution, we may find a way to incorporate biometrics into our lives and still maintain our privacy.

Case Leads: A Forensicator's take on BlackHat/DefCon/BSides

Case Leads: A Forensicator's take on BlackHat/DefCon/BSides

It's been a busy time in digital forensics and incident response (DFIR). Every summer, for over 20 years, infosec and forensicators and old school hackers have gathered in Las Vegas. A mixture of very deep tech talks, trainings, and technology oriented distractions "flood the zone" in Las Vegas. Close to 15-20,000 people were in Las Vegas this summer for what has now evolved into three separate conferences, all in the same week.

July 27th was the start of Black Hat at Caesars Palace in Las Vegas. The conference kicks off with training in the last weekend of the month, and finishes on Wednesday, July 31st and Thursday, August 1st, with lectures and technical demonstrations, called "Black Hat Briefings." This year, in the wake of the NSA/Snowden rowe, NSA Director, General Keith Alexander gave the opening keynote. Black Hat was more corporate than ever, with more sponsor banners, and sponsor-generated talks (disclosed by the organizers, and placed in a separate area, bravo!) than ever. Black Hat moves next year to the south end of the Las Vegas strip, at the Mandalay Bay. Some have speculated that the larger vendor area was part of the motivation. A spokesperson for Black Hat stated simply, "We need more room."

Meanwhile, two and a half blocks east of Ceasars Palace, at the Tuscany Hotel Casino, BSides Las Vegas was running during the same Wednesday and Thursday as Black Hat. BSides was a real gem this year. Great crowd, with many very smart and interesting speakers, lectures and labs. One of the more compelling DFIR talks of the week was a demonstration on defeating application whitelisting, and the digtial forensic trail that this incident leaves behind. See Good Reads and Listens below for an interview with the co-presenter of that talk, Joe Kovacic.

Thursday August 1st was the "soft launch" of DefCon 21, at the Rio Casino, just west of the Las Vegas Strip. Of note: Def Con held legal training on Thursday for non-legal professionals on the fundamentals of civil and criminal law. Always a help for forensicators. Sunday was the unofficial "forensicator block," with three lectures covering forensics, including an interesting talk on the recoverability of "disappearing" messages like SnapChat. Another DefCon talk relevant for incident response, was Craig Young's talk on a critical authentication flaw in GoogleAppsGmailAndroid. See Good Reads and Listens below for an interview with Craig Young.

If you have an item you'd like to contribute to Digital Forensics Case Leads, please send it to kuyasamahbub@gmail.com.

Tools:

• Mr. John Ortiz developed and teaches a steganography course for the University of Texas at San Antonio (UTSA). Mr. Ortiz developed several steganographic programs for testing and analysis that were demonstrated at DefCon 21 in Las Vegas this year, during the unofficial forensicator block. You may email John: stego [insert at symbol here] satx.rr.com for details on how to obtain these free tools.
• Belkasoft Evidence Center 5.4 (Updated), Detects Forged Images, Analyzes Fragmented Memory Dumps and Extracts Destroyed SQLite Records
• BlackBag Technologies Announces BlackLight2013 R2 Cross-platform Forensics Software Release

Good Reads and Listens:

• From The Ponemon Institute: Live Threat Intelligence Impact Report 2013
• NSA Director Gen. Alexander, in his keynote address on the opening day of Black Hat Briefings Las Vegas
• An interview with Craig Young, taped on the floor of DefCon 21, on his forensic research into a critical authentication flaw in GoogleAppsGmailAndroid
• An interview with Joe Kovacic, taped on the floor of BSides LV, on his research into defeating application whitelisting, and the digtial forensic trail that a breach might leave behind
• An interview with Richard Hickman, who wrote a paper based upon his digital forensic work on SnapChat. The "defeating" SnapChat session at the unofficial forensicator block at DefCon was standing room only. Related story in the news section below.

News:

• 'Snap Save,' a new iPhone app, let's users same SnapChats, without alerting the sender
• Interesting meta data that could prove useful in investigations: Study: Cellular mobile devices emit a traceable meta data digital fingerprint beyond the SIM chip
• Forensicators help determine that is was malware that led to the collapse of a California financial escrow firm
• War on US Cloud Providers: How the US Government Killed a Texas-based Secure E-mail Company
• War on US Cloud Providers II: NSA scandal could cost the US cloud computing industry up to $35 billion over the next three years, a new report claims
• War on US Cloud Providers III: Germany's leading telecoms operator will channel email traffic exclusively through its domestic servers in response to public outrage over U.S. spy programs accessing citizens' private messages. But, Crypto experts blast the German e-mail providers' "secure data storage" claim

Levity: 

  DEF CON: The Documentary, the complete movie. Filmed last year, the 20th anniversary of DefCon. Shown at DefCon 21, August 1, 2013.

 

© Kuyasa Mahbub