This chapter is from the book
This chapter is from the book
This chapter is from the book
Mobile Security
Mobile devices need to be secure just like any other computing devices. But due to their transportable nature, some of the security techniques will be a bit different. I recommend that you prepare for the possibility of a stolen, lost, damaged, or compromised device. The following methods can help you to recover from these problems and also aid you in preventing them from happening.
Stolen and Lost Devices
Because mobile devices are expensive and could contain confidential data, they become a target for thieves. Plus, they are small and easy to conceal, making them easier to steal. But there are some things you can do to protect your data and attempt to get the mobile device back.
The first thing a user should do when receiving a mobile device is to set a passcode, which is a set of numbers. This is one of several types of screenlocks. Locking the device makes it inaccessible to everyone except experienced hackers. The screen lock can be a pattern that is drawn on the display, a PIN (passcode), or a password. A strong password will usually be the strongest form of screenlock.
This can be accessed on an Android device by going to Settings > Security. This screen on a typical Android smartphone is shown in Figure 17.13.
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Figure 17.13. Android security screen
You can also select how long the phone will wait after inactivity to lock. Generally this is set to 3 or 5 minutes or so, but in a confidential environment you might set this to Immediate.
The next option on the Security screen is Visible Passwords. If check marked, this shows the current letter of the password being typed by the user. This type of setting is vulnerable to shoulder surfers (people looking over your shoulder to find out your password) and should be deselected. When deselected, only asterisks (*) are shown when the user types a password.
Passcode locking can be accessed on an iPad device by going to Settings > General > and tapping Passcode Lock. This displays the Passcode Lock screen. Tap Turn Passcode On to set a passcode, as shown in Figure 17.14. Be sure that the Auto-Lock on the previous screen is set to an amount of minutes. If it is set to Never, the device never sleeps, negating the security of the passcode, and using valuable battery power. The default setting is 2 minutes. You’ll also note in Figure 17.14 that Simple Passcode is enabled. This allows 4-digit numeric passcodes only. As this is probably not going to be secure enough for an organization, you should turn the Simple Passcode option off; that will allow alphanumeric passwords to be entered.
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Figure 17.14. iPad2 passcode lock screen
Aside from the default timeout, devices can also be locked by pressing the power button quickly. If configured, the passcode must be supplied whenever a mobile device comes out of a sleep or lock state and whenever it is first booted.
If a person fails to enter the correct passcode after a certain amount of attempts, the device locks temporarily and the person has to wait a certain amount of time before attempting the passcode again. For example, by default on the Android this is 5 attempts; if they all fail the user has to wait 30 seconds. If the person fails to enter the correct passcode again, the timeout increases on most devices. After a certain amount of attempts, the device either needs to be connected to the computer it was last synced to, or has to be restored to factory condition with a hard reset (which can wipe the data.)
Some devices (such as the iPhone) have a setting where the device will be erased after a certain amount of incorrect password attempts (10 in the case of the iPhone). There are also third-party apps available for download for most mobile devices that can wipe the data after x number of attempts. Some apps configure the device to automatically take a picture after 3 failed attempts and e-mail the picture to the owner.
There’s an app for virtually everything. For example, say the device was lost or stolen. If the user had previously installed a locator application, such as Where’s my Droid, Lookout Mobile Security, or Find iPhone, and the GPS/Location Services was enabled on the device, then the user would track where the device is. At that point, the organization would decide whether to get the police involved.
Now, even if you track your mobile device and find it, it might be too late. A hacker can get past passcodes and other screen locks. It’s just a matter of time before the hacker has access to the data. So, an organization with confidential information should consider a remote wipe program. As long as the mobile device still has access to the Internet, the remote wipe program can be initiated from a desktop computer, which will delete all the contents of the remote mobile device. Examples of software that can accomplish this include: Google Sync, Google Apps Device Policy, Apple’s Data Protection, and third-party apps such as Mobile Defense. In some cases, such as Apple’s Data Protection, the command that starts the remote wipe must be issued from an Exchange server or Mobile Device Management server.
You should also have a backup plan in place as well so that data on the mobile device is backed up to a secure location at regular intervals. This way, if the data needs to be wiped, you are secure in the fact that most of the data can be recovered. The type of remote wipe program, backup program, and policies regarding how these are implemented will vary from one organization to the next. Be sure to read up on your organization’s policies to see exactly what is allowed from a mobile security standpoint.
Compromised and Damaged Devices
Theft and loss aren’t the only risks a mobile device faces. We should protect against the chance that a mobile device is damaged, or if the device’s security is compromised.
Many organizations implement backup and remote backup policies. iOS devices can be backed up to a PC via USB connection and by using iTunes. Also, they can be backed up remotely to the iCloud. In addition, there are other third-party apps for remote backup such as iDrive and Mozy. Information can even be restored to newer, upgraded iOS devices. Android (as of the writing of this book) doesn’t allow a complete backup without rooting the phone (which I don’t recommend.) However, almost all the data and settings can be backed up in a collection of ways. First, the Android Cloud backup can be used to backup e-mail, contacts, and other information. However, if you use Gmail, then e-mail, contacts, and calendars are backed up (and synchronized) to Google servers. If a mobile device is lost, the information can be quickly accessed from a desktop computer or other mobile device. Unlike Apple, Android applications can be backed up, as long as they are not copy-protected, with an app such as Astro. Android settings can be backed up and restored from Settings > Privacy. If you choose not to use the Android cloud to backup files, or the synchronization program that came with the device, then there are plenty of third-party apps (such as iDrive, Mozy, HandyBackup, and so on) that can be used to backup via USB to a PC, or to backup to the cloud.
One way to protect mobile devices from compromise is to patch or update the operating system. By default, you will be notified automatically about available updates on Android and iOS-based devices. However, you should know where to go to manually update these devices as well. For Android go to Settings > System Updates > Software Update (or similar path). From here tap Check Now. If you have a connection to the Internet, you will receive any information concerning system updates; an example is shown in Figure 17.15.
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Figure 17.15. Android system update available
As you can see in the figure, the system update has an important new security feature that should be installed right away (which I will do when I finish writing this sentence!) Security patches are a large percentage of system updates because there are a lot of attackers around the world that want to compromise the Android operating system. But let’s be real—attackers will go for any OS if it catches their fancy, be it Android, iOS or even Windows!
Updates for iOS can be located at Settings > General > Software Update. As shown in Figure 17.16, this iOS needs to be updated from 5.0 to 5.1 and should be done as soon as possible to patch up any security flaws, and make the best use of the system.
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Figure 17.16. iOS system update available
Updates are great, but they are not created to specifically battle viruses and other malware. So, just like there is antivirus software for PCs, there is also AV software for mobile devices. These are third-party applications that need to be paid for, downloaded, and installed to the mobile device. Some common examples for Android include McAfee’s Virusscan Mobile, AVG, Lookout, Dr. Web, and NetQin.
iOS works a bit differently. iOS is a tightly controlled operating system. One of the benefits of being a closed-source OS is that it can be more difficult to write viruses for, making it somewhat more difficult to compromise. But there is no OS that can’t be compromised. For the longest time there was no antivirus software for iOS. That is until 2011 when a type of jailbreaking software called jailbreakme used a simple PDF to move insecure code to the root of the device causing a jailbreak.
Jailbreakme is used to gain root level access and take control of the device without the user’s consent. Finally, Apple consented to the first antivirus software for iOS, Intego’s VirusBarrier, a paid download through the App Store. Any AV software for Android or iOS should be checked regularly for updates.
For large organizations that have many mobile devices, a Mobile Device Management (MDM) suite can be implemented. McAfee, and many other companies from AirWatch to LANDesk Mobility Manager to Sybase, have Mobile Device Management software suites that can take care of pushing updates and configuring hundreds of mobile devices from a central location. Decent quality MDM software will secure, monitor, manage, and support multiple different types of mobile devices across the enterprise.
Stopping Applications
Applications that are opened on a mobile device will continue to run in the background unless they are specifically turned off within the app or within the OS.
To turn off apps (or services) that are running on an Android-based system, go to Settings > Applications > Running Services. That displays all the currently running services and applications, as shown in Figure 17.17.
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Figure 17.17. Services and apps running on an Android
You can see in the figure that there are several apps and services running including the droid VNC server, Calendar, and a GPS program. To see all the services and apps, just scroll down. As with PCs, mobile device apps use RAM. The bottom of the figure shows that 194 MB of RAM is currently being used, and 139 MB of RAM is free. The more RAM that is used by the mobile device, the worse it will perform: it will slow it down, and eat up battery power. So, to close an app, you would simply tap it and tap Stop. You can also stop services or processes in this manner (for example HTC DM in the figure), but this might require a Force Stop. If you are not absolutely sure what the service is, do not initiate a Force Stop, as it can possibly cause system instability.
To force quit an app on an iOS-based device, press and hold the Sleep/Wake button for a few seconds until a red slider appears. Then press and hold the home button until the app quits.
There are third-party apps that can close down all of the apps in one shot if you need to save time. These include Task Manager, TasKiller, and AppControl.
If an application is causing the device to lock up and you can’t stop the app, a soft reset or a hard reset will be necessary.
Initiating Resets
A soft reset is done by simply powering off the mobile device and powering it back on. This resets the drivers and the OS. So, soft resets are similar to shutting down a PC and powering it back up. Some technicians will also call this a power cycle. The soft reset can help when certain applications are not functioning properly, or if network connectivity is failing. If a smartphone is still locked up when it is restarted, try pulling the battery, replacing it, and restarting the phone again. In fact, for Blackberry devices, soft resets require a battery pull.
iOS-based devices can do a variety of more advanced software resets beyond a simple power-cycle, such as Reset All Settings, Erase All Content, Reset Networking settings, and so on. These are available by tapping Settings > General > Reset.
Hard resets should be initiated only when things have gone terribly wrong. For example, if hardware or software has been compromised, or has failed, and a soft reset does not fix the problem. You want to make sure that all data is backed up before performing a hard reset, as some hard resets will reset the mobile device back to the original factory condition.
Hard resets vary from one device to the next. For example, most Android-based systems such as the HTC smartphone mentioned previously use the following steps:
- Turn the power off. If the device is locked (frozen), pull the battery out and reinsert it.
- Hold the Volume Down button, and press and release the Power button.
- This displays a menu that allows for Fastbook, Recovery, Clear Storage, and Simlock. Select Clear Storage by pressing the Volume Down button.
- Press and release the Power button.
- Confirm by pressing Volume Up for Yes or Volume Down for No.
At this point, the device will be reset and you will have to restore data and settings from backup.
Unlike many other mobile devices, hard resets on iOS-based devices do not delete data. They instead stop all apps, and reset the OS and drivers. This can be accomplished with the following steps:
- Make sure that the device has at least 20 percent battery life remaining. (This process could take some time, and you don’t want the battery to discharge completely in the middle of it.)
- Press the Sleep/Wake and Home buttons simultaneously for 10 seconds or until the Apple logo appears. (Ignore the red slider).
- When the logo appears, the hard reset has been initiated. It may take several minutes to complete.
To fully reset an iOS-based device such as the iPad2 to factory condition, you need to go to Settings > General > Reset > Erase all Content and Settings. Another way to do this is to connect the iOS device to a computer via USB and open iTunes on the computer. Then, select the iPad2 option, Summary, and click Restore. Regardless of the method you choose, next, initiate a hard reset to complete the procedure.
As you have seen with Android and Apple, the types of resets vary from one device to the next, so be sure to go to the manufacturer’s website to find out exactly what the various resets do for your mobile device, and how you can perform them.
Cram Quiz
Answer these questions. The answers follow the last question. If you cannot answer these questions correctly, consider reading this section again until you can.
220-802 Questions
-
You want to prevent a person from accessing your phone while you step away from your desk. What should you do?
A.
Implement remote backup.
B.
Set up a remote wipe program.
C.
Configure a screen lock.
D.
Install a locator application.
-
What does the iOS Simple Passcode allow a person to enter?
A.
4-letter code
B.
6-number PIN
C.
4-digit passcode
D.
Alpha-numeric passcode
-
What do third-party apps such as Find iPhone rely on?
A.
Passcode
B.
Google Apps Device Policy
C.
Bluetooth
D.
GPS
-
Which of the following can be described as removing limitations on iOS?
A.
Rooting
B.
Jailbreaking
C.
Geotracking
D.
AV software
-
An application won’t close on an Android smartphone. You’ve tried to Force Stop it to no avail. What should you do?
A.
Hard reset the device.
B.
Stop the service in Running Services.
C.
Soft reset the device.
D.
Bring the device to an authorized service center.
-
Your organization is concerned about a scenario where a mobile device with confidential data is stolen. What should you recommend first? (Select the best answer.)
A.
Remote backup application
B.
Remote wipe program
C.
Passcode locks
D.
Locator application
-
You are concerned with the possibility of jailbreaks on your organization’s iPhones, and viruses on the Android-based devices. What should you implement?
A.
AV software
B.
Firewall
C.
Mobile Device Management
D.
Device reset
Cram Quiz Answers
220-802 Answers
- C. You should configure a screen lock: either a pattern drawn on the screen, a PIN, or a password. Remote backup, remote wipe, and locator applications will not prevent a person from accessing the phone.
- C. The iOS Simple Passcode allows only a 4-digit numeric passcode. To enter alpha-numeric passwords, you need to disable Simple Passcode.
- D. Third-party locator apps such as Find iPhone and Where’s my Droid rely on GPS to locate the device. Passcodes are used to prevent unauthorized users from accessing the mobile device. Google Apps Device Policy can initiate a remote wipe on a mobile device. Bluetooth is used so the mobile device can communicate with other devices over short range.
- B. Jailbreaking is the process of removing the limitations of an iOS-based device so that the user gets superuser abilities. Rooting is a similar technique used on Android mobile devices. Geotracking is the practice of tracking a device over time. AV software is antivirus software, used to combat malware.
- C. If you’ve already tried to stop the application within Running Services, attempt a soft reset. Pull the battery if the application is frozen. Hard resets on Android devices should be used only as a last resort as they will return the device to factory condition—wiping all the data. The question said that the application won’t close, not a service, though you could try finding an underlying service that might be the culprit. But try resetting the device before doing this or bringing it to an authorized service center.
- B. The remote wipe application is the most important one listed. This will prevent a thief from accessing the data on the device. Afterward, you might recommend a backup program (in case the data needs to be wiped), as well as passcode locks and a locator application.
- A. You should implement antivirus (AV) software. This can protect against viruses and other malware as well as jailbreaks on Apple devices. As of the writing of this book, firewalls for mobile devices are not common, but that could change in the future. Mobile Device Management (MDM) is software that runs at a central computer enabling a user to configure and monitor multiple mobile devices. Device resets are used to restart the mobile device, or to reset it to factor condition depending on the type of reset, and the manufacturer of the device.