Introduction to Cyber Security



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Introduction-cyber-security

Open Secure Telephony Network (OSTN) and the server provided by the Guardian project, ostel.co, currently offers one of the most secure means to communicate via voice. Knowing and trusting the entity that operates the server for your VoIP communication needs is an important consideration.
When using CSipSimple, you never directly communicate with your contact, instead all your data is routed through the Ostel server. This makes it much harder to trace your data and find out who you are talking to. Additionally, Ostel doesn't retain any of this data, except the account data that you need to log in. All your speech is securely encrypted and even your meta data, which is usually very hard to disguise, is blurred since traffic is proxied through the ostel.co server. If you download CSipSimple from ostel.co it also comes preconfigured for use with ostel, which makes it very easy to install and use.
Tool Guides for CSipSimple and Ostel.co are forthcoming. In the meantime, more information can be found by following the links above.
        1. Sending Messages Securely

You should use precautions when sending SMS and using instant messaging or chatting on your smartphone.

SMS


SMS communication is insecure by default. Anyone with access to a mobile telecommunication network can intercept these messages easily and this is an everyday occurrence in many situations. Don't rely on sending unsecured SMS messages in critical situations. There is also no way of authenticating SMS messages, so it is impossible to know if the contents of a message was changed during delivery or if the sender of the message really is the person they claim to be.
Securing SMS

TextSecure is a FOSS tool for sending and receiving secure SMS on Android phones. It works both for encrypted and non-encrypted messages, so you can use it as your default SMS application. To exchange encrypted messages this tool has to be installed by both the sender and the recipient of a message, so you will need to get people you communicate with regularly to use it as well. TextSecure automatically detects when an encrypted message is received from another TextSecure user. It also allows you to send encrypted messages to more than one person. Messages are automatically signed making it nearly impossible to tamper with the contents of a message. In our TextSecure hands-on guide we explain in detail the features of this tool and how to use it.
Secure Chat

Instant messaging and chatting on your phone can produce a lot of information that is at risk of interception. These conversations might be used against you by adversaries at a later date. You should therefore be extremely wary about what you reveal when you are writing on your phone while instant messaging and chatting.
There are ways to chat and instant message securely. The best way is to use end-to-end encryption, as this will enable you to make sure the person on the other end is who you want.
We recommend ChatSecure as a secure text chat application for the Android phones. ChatSecure offers easy and strong encryption for your chats with Off-the-Record Messaging protocol. This encryption provides both authenticity (you can verify that you are chatting with the right person) and the independent security of each session so that even if the encryption of one chat session is compromised, other past and future sessions will remain secure.
ChatSecure has been designed to work together with Orbot, so your chat messages can be routed through the Tor anonymizing network. This makes it very hard to trace it or even find out that it happened.
For iPhones, the ChatSecure client provides the same features, although it is not easy to use it with the Tor network.
Whichever application you will use always consider which account you use to chat from. For example when you use Google Talk, your credentials and time of your chatting session are known to Google. Also agree with your conversation partners on not saving chat histories, especially if they aren't encrypted.
        1. Storing Information on your Smartphone

Smartphones come with large data storage capacities. Unfortunately, the data stored on your device can be easily accessible by third parties, either remotely or with physical access to the phone. You can take steps to encrypt any sensitive information on your phone by using specific tools.
Date Encryption Tools

The Android Privacy Guard (APG) allows OpenGPG encryption for files and emails. It can be used to keep your files and documents safe on your phone, as well when emailing.
Recording Password Securely

You can keep all your needed passwords in one secure, encrypted file by using Keepass. You will only need to remember one master password to access all the others. With Keepass you
can use very strong passwords for each account you have, as Keepass will remember them for you, and it also comes with a password generator to create new passwords. You can synchronise Keepass password databases between your phone and your computer. We recommned that you synchronise only those passwords that you will actually use on your mobile phone. You can create a separate smaller password database on the computer and syncronise this one instead of coping an entire database with all the passwords that you use to your smartphone. Also, since all the passwords are protected by your master password, it is vital to use very strong password for your Keepass database.
        1. Sending Email from your Smartphone

In this section we will briefly discuss the use of email on smartphones. In the first instance, consider if you really need to use your smartphone to access your email. Securing a computer and its content is generally simpler than doing so for a mobile device such as a smartphone. A smartphone is more susceptible to theft, monitoring and intrusion.
If it is absolutely vital that you access your email on your smartphone, there are actions you can take to minimize the risks.

  • Do not rely on smartphone as your primary means for accessing your email. Downloading (and removing) emails from an email server and storing them only on your smartphone is not advised. You can set up your email application to use only copies of emails.

  • If you use email encryption with some of your contacts, consider installing it on your smartphone, too. The additional benefit is that encrypted emails will remain secret if the phone falls into wrong hands.

Storing your private encryption key on your mobile device may seem risky. But the benefit of being able to send and store emails securely encrypted on the mobile device might outweigh the risks. Consider creating a mobile-only encrytpion key-pair (using APG) for your use on your smartphone, so you do not copy your encryption private key from your computer to the mobile device. Note that this requires that you ask people you communicate with to also encrypt emails using your mobile-only encryption key.
        1. Capturing Media with your Smartphone

Capturing pictures, video or audio with your Smartphone can be a powerful means to document and share important events. However, it is important to be careful and respectful of privacy and safety of those pictured, filmed or recorded. For example, if you take photos or record video or audio of an important event, it might be dangerous to you or to those who
appear in the recordings, if your phone fell into the wrong hands. In this case, these suggestions may be helpful:

          • Have a mechanism to securely upload recorded media files to protected online location and remove them from the phone instantly (or as soon as you can) after recording.

          • Use tools to blur the faces of those appearing in the images or videos or distort the voices of audio or videos recordings and store only blurred and distorted copies of media files on your mobile device.

          • Protect or remove meta information about time and place within the media files. Guardian Project has created a FOSS app called ObscuraCam to detect faces on photos and blur them. You can choose the blurring mode and what to blur, of course. Obscuracam also deletes the original photos and if you have set up a server to upload the captured media, it provides easy functionality to upload it.
        1. Accessing the Internet Securely from your Smartphone

As discussed in our guide How to keep your Internet communication private and our guide How to remain anonymous and bypass censorship on the Internet, access to content on the Internet, or publishing material online such as photos or videos, leaves many traces of who and where you are and what you are doing. This may put you at risk. Using your smartphone to communicate with the Internet magnifies this risk.
Through Wi-Fi or Mobile Data

Smartphones allow you to control how you access the Internet: via a wireless connection provided by an access point (such as an internet cafe), or via a mobile data connection, such as GPRS, EDGE, or UMTS provided by your mobile network operator.
Using a WiFi connection reduces the traces of data you may be leaving with your mobile phone service provider (by not having it connected with your mobile phone subscription). However, sometimes a mobile data connection is the only way to get online. Unfortunately mobile data connection protocols (like EDGE or UMTS) are not open standards. Independent developers and security engineers cannot examine these protocols to see how they are being implemented by mobile data carriers.
In some countries mobile access providers operate under different legislation than internet service providers, which can result in more direct surveillance by governments and carriers.
Regardless of which path you take for your digital communications with a smartphone, you can reduce your risks of data exposure through the use of anonymising and encryption tools.
Anonymity of your Smartphone

To access content online anonymously, you can use an Android app called Orbot. Orbot channels your internet communication through Tor's anonymity network.
Another app, Orweb, is a web browser that has privacy enhancing features like using proxies and not keeping a local browsing history. Orbot and Orweb together circumvent web filters and firewalls, and offer anonymous browsing.
Proxies

The mobile version of Firefox Firefox mobile can be equipped with proxy add-ons, which direct your traffic to a proxy server. From there your traffic goes to the site you are requesting. This is helpful in cases of censorship, but still may reveal your requests unless the connection from your client to the proxy is encrypted. We recommend the Proxy Mobile add- on (also from Guardian Project, which makes proxying with Firefox easy. Is also the only way to channel Firefox mobile communications to Orbot and use the Tor network.
        1. Advanced Smart Phone Security
Get Full Access to your Smartphone

Most Smartphones are capable of more than their installed operating system, manufacturers' software (firmware), or the mobile operators' programmes allow. Conversely, some functionalities are 'locked in' so the user is not capable of controlling or altering these functions, and they remain out of reach. In most cases those functionalities are unnecessary for smartphone users. There are however, some applications and functionalities that can enhance the security of data and communications on a smartphone. Also there are some other existing functionalities that can be removed to avoid security risks.
For this, and other reasons, some smartphone users choose to manipulate the various software and programs running the smartphone in order to gain appropriate privileges to allow them to install enhanced functionalities, or remove or reduce other ones.
The process of overcoming the limits imposed by mobile carriers, or manufacturers of operating systems on a smartphone is called rooting (in case of Android devices), or jailbreaking (in case of iOS devices, like iPhone or iPad). Typically, successful rooting or jailbreaking will result in your having all the privileges needed to install and use additional
applications, make modifications to otherwise locked-down configurations, and total control over data storage and memory of the smartphone.
WARNING: Rooting or jailbreaking may not be a reversible process, and it requires experience with software installation and configuration. Consider the following:



  • There is a risk of making your smartphone permanently inoperable, or 'bricking' it (i.e. turning it into a 'brick').

  • The manufacturer or mobile carrier warranty may be voided.

  • In some places, this process maybe illegal.

But if you are careful, a rooted device is a straightforward way to gain more control over your smartphone to make it much more secure.


Alternative Firmwares

Firmware refers to programmes that are closely related to the particular device. They are in cooperation with the device's operating system and are responsible for basic operations of the hardware of your smartphone, such as the speaker, microphone, cameras, touchscreen, memory, keys, antennas, etc.
If you have an Android device, you might consider installing a firmware alternative to further enhance your control of the phone. Note that in order to install alternative firmware, you need to root your phone.
An example of an alternative firmware for an Android phone is Cyanogenmod which, for example, allows you to uninstall applications from the system level of your phone (i.e. those installed by the phone's manufacturer or your mobile network operator). By doing so, you can reduce the number of ways in which your device can be monitored, such as data that is sent to your service provider without your knowledge.
In addition, Cyanogenmod ships by default with an OpenVPN application, which can be tedious to install otherwise. VPN (Virtual Private Network) is one of the ways to securely proxy your internet communication (see below).
Cyanogenmod also offers an Incognito browsing mode in which history of your communication is not recorded on your smartphone.
Full Device Encryption

If your phone is rooted you may consider encrypting it's entire data storage or creating a volume on the Smartphone to protect some information on the phone.

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