Tag: confidential communications

What can be done to support secure email?

Personal and business Internet users are showing interest in the concept of secure email. This is to assure that confidential emails only end up being viewed by the eyes of their intended recipients.

It is being driven by issues relating to confidential personal and business information being leaked to the Web along with a common personal worry regarding government surveillance in the age of terrorism and extremism. Along with this, activists, journalists and the like are wanting to rely on secure communications to pass through critical information in areas that are hostile to freedom of speech and the press. In some cases, people travelling through countries known to be hostile to freedom of speech like Russia and China have been encouraged to keep their data highly secure due to the espionage taking place in these countries.

Compose Email or New Email form

More work needs to be done on secure email

There is a slow increasing prevalence of secure email platforms appearing on the Web. These platforms such as the Swiss-based ProtonMail and the secure iteration of Google’s GMail service are dependent on a Web-based user interface. Along with this, most of us are implementing instant-messaging platforms like WhatsApp, Viber and Telegram to send personally-confidential material to each other.

But they offer a series of features intended to assure personal privacy and corporate data security. They offer end-to-end encryption for the emails at rest (while they are on the servers pending delivery) and in transit (while they are being moved between servers). They also offer the ability for users to send seif-destructing emails that don’t stay in the recipient’s or the sender’s storage space after they are read unlike with conventional emails which stay in the user’s storage space after being sent or read. These self-destructing emails cannot even be forwarded to others or printed out (although it could be feasible to take a screenshot of that email and print or forward it). Some of these setups even have the ability to detect screenshots and let the sender know if the recipient took one of a confidential email. As well the metadata about the emails isn’t held on the servers.

But there are current limitations associated with these services. One of these is that the privacy features are only available to users who subscribe to the same email platform. This is because the common standards for secure email such as S/MIME, PGP and GnuPG only support basic key-based encryption and authentication abilities and the common email protocols like IMAP and POP3 don’t support email-handling control at the message level. As well, these services rely on a Webmail interface and require users to click on links sent as part of standard emails to view the secure messages if they aren’t part of that system.

There are certain features that need to be added to IMAP4 to allow for secure email handling. One of these is to permit message-level email control to permit self-destructing emails and to allow the sender to limit how the recipient can handle the messages. But the message-control features may run against legal-archive and similar requirements that will be asked of for business correspondence. In this situation, there may be the ability to indicate to senders or recipients if the emails are being archived as a matter of course and message-level email control can’t be assured.

Of course this may be about a newer feature-level email standard, preferably open-source or managed by many in computing academia and industry, to add this kind of secure email control.

Then there is the requirement to encourage the use of encrypted-email / authenticated-email standards like S/MIME or PGP within email endpoints, both Web-based and client-based. It will also include the ability for users to create asymmetrical key pairs and store their correspondents’ public keys in their contact manager software. There will also have to be the ability to support automated public-key discovery as a new contact is added, something currently feasible with encrypted messaging platforms that maintain their own contact directory.

Other questions that will come up in the course of building a secure email ecosystem is how the encryption keys are stored on the end-user’s system and whether an end-user needs to create new encryption keys when they change devices along with how to store them securely. This can be of concern with most computer users who typically maintain multiple devices, typically a smartphone along with a regular desktop or laptop computer and / or a tablet of the iPad ilk. Similarly there is the fact that one may not have the same computing device for the long haul, typically due to replacing one that has broken down or upgrading to a better-performing device.

There will also have to be the issue of security and portability thanks to issues like users temporarily using different computer devices such as friends’ computers, work / school computers or public computers. Here, it may be a question about where contact-specific encryption keys are held, whether on a server or on removable media along with how email sessions are handled on these temporary setups.

What will need to happen is for email platforms to support various secure-messaging features in a manner that can exist on a level playing field and without the need for correspondents to be on the same provider.

Popular Internet-based communications platforms to be secure

WhatsApp Android screenshot courtesy of WhatsApp

WhatsApp – the pioneer for security-focused online communications for consumers

Some of the popular over-the-top messaging and VoIP platforms are being equipped for personal privacy and security.

This was a feature typically pitched at high-stakes business users but is now being pitched at everyday consumers thanks to the saga occurring in the USA between FBI and Apple where the FBI were wanting the encrypted data held on a suspect’s iPhone.

At the moment, WhatsApp and Viber are offering secure-communications features but this could be rolled out by other messaging/VoIP/videocall platform vendors like Skype, Facebook or Apple. For that matter, WhatsApp have recently made their platform from a subscription-funded platform to a free-to-user platform. They will continue to raise money by offering business-focused WhatsApp communications services.

Platform-wide best-case encryption by default

One of the main features is platform-wide end-to-end encryption which is implemented to “best-case standards” by default.

This means that the data that represents your calls and messages is encrypted by the end devices. Along with that, the user’s public and private keys associated with the encryption algorithm don’t stay on the company’s servers, thus not being at risk of a subpoena or other court order or government mandate. Rather, these are created by the end-user’s device and kept there.

The reference to “best-case” operation in this situation is that if the users are communicating with the latest version of the software that supports newer encryption algorithms, these algorithms are used for the encryption process. This even applies to group conversations where the “best-case” encryption method is implemented if all the correspondents are using the client apps that support that algorithm.

Authentication of contacts and their devices

As part of key exchange between contacts, there is an emphasis on authenticating one’s contacts with some systems like WhatsApp preferring a “face-to-face” method or others like Viber requiring you to read and confirm a password during a call. The former method that WhatsApp implements is for you to scan a QR code

Here, this is about whether you are really talking with the user on their device, in order to circumvent situations like lost or stolen phones, users installing their SIM cards in different devices and “man-in-the-middle” attacks. It was highlighted in Graham Cluley’s blog article about improving your security with WhatsApp.

This will typically be highlighted through the use of an indicator in your contact list that shows if a contact has been authenticated or if they have switched devices.

Concealed text/image conversations

Viber - Hide This Chat

Viber with its ability to conceal a conversation

Viber introduced to their platform the ability for one to conceal a text/image conversation which can come in handy if you are exploiting their functionality to use tablets or regular computers as endpoints for Viber conversations.

Here, you can conceal the conversation so that others cannot see it unless they enter a user-set PIN or password. Situations where this can be necessary could include an innocuous activity like arranging that surprise event through a personal conversation held in a workplace to a traveller who leaves their iPad in their hotel room which can easily be visited by Housekeeping staff.

On the other hand, you could be able to specify whether a text/image chat is to be kept on each other’s devices or to disappear like what has been valued with Snapchat.

Features that could surface in the name of security

As other online-communications platforms jump on to the secure-communications bandwagon, there could be the rise of different features or variations on the above features.

For example, a communications-platform client could implement client-level user authentication where the software can be set up to require the user to log in to the client to start a conversation. Or the primary communications device like the smartphone has to be near a secondary communications client like a laptop before the user can run the software. This feature may be considered of importance with tablets and regular computers likely to be used by other users.

To some extent, an operating system that implements multiple-user operation could allow an online-communications client to switch user profiles and phone numbers so it works totally personally to the user.

There could be the ability for a user to mandate device-level authentication or encryption before a conversation takes place with a contact. This could allow for one to be sure they are talking to the right correspondent.

Other methods of verifying contacts and devices could surface such as the use of NFC “touch-and-go” or Bluetooth data exchange as a way of authenticating users’ devices. The software could also exploit other hardware or software “secure elements” like Trusted Platform Modules as an alternative to SIM cards for Wi-Fi-only tablets or regular computers.

This could even extend to such things as “trusted networks” or “trusted locations” where your caller can know that you are talking privately, based on factors like wireless-network parameters or proximity to particular Bluetooth devices.

Conclusion

What is now happening is that secure online conversations, once a feature that was enjoyed by big business and government, is now becoming available to every individual in the street for free. This allows them to have online conversations without being eavesdropped upon.