Why should you encrypt email?
As a communication method and for sharing data, email is as popular as ever. Despite the influx of other messaging and online file sharing solutions, it remains the most widely used tool for organisations to transmit and receive sensitive data
However, standard email was never designed with security in mind, and so default email systems are characteristically insecure. Coupling this with greater information security risk than ever before, emails are an increasingly vulnerable target for both external attackers and insider threats.
Using encryption can mitigate these risks, but encrypting email can mean different things. This article explains why, and how, you should encrypt your email communications.
Where can email be compromised?
Without encryption, your emails can potentially be accessed by third parties at different points in the email journey.
- Someone with access to your device will be able to access your emails if they are not encrypted at rest. The same applies if any archiving software you use stores the emails unencrypted.
- Additionally, it’s crucial to encrypt the connection between your device and your email provider, to prevent other users gaining access to the communications or intercepting your sent and received email messages.
- The servers of your email provider also require effective security to prevent infiltration, including additional authentication measures, such as Multi-Factor Authentication to stop attackers gaining access to your emails using stolen credentials.
- Vulnerability at the recipient end also presents a security threat. Your recipient’s device, connections and email provider can all be hijacked by an unauthorised user, giving them the ability to read your email communications.
How to encrypt email to protect against outsider attacks
Without adequate email encryption in place, each stage of an email’s journey from sender to recipient is vulnerable to outside attacks.
Encrypting email can significantly lower the chances of a hacker gaining access to the sensitive data within your emails. If they employ a combination of message-level encryption with Transport Layer Security (TLS), users can encrypt both the message and the channel used to send it to the recipient. In tandem, these two encryption methods can frustrate any potential unauthorised access attempts, and even if TLS fails for any particular reason, each message will still be encrypted. Many message-level encryption solutions exist; some can be complex to implement, but others are more user friendly.
How to encrypt email to prevent data breaches
There are different causes of data breaches, from the malicious outsider attack as mentioned above, to the insider threat. This can be both targeted and accidental, as an internal user releases sensitive information outside a restricted domain. The user can intentionally email organisational data that should have restricted access to an unauthorised recipient, but this can also be inadvertent. The accidental send, where the user sends sensitive data to the wrong recipient, is an all too common occurrence and a major cause of data breaches.
Data breaches can cause serious harm to an organisation over and above the initial loss of data. Financial penalties can be huge, but reputational damage can often be much worse in the long run. Hence, there is a real need to prevent data breaches. To do this, as well as encrypting email, users need to be able to constantly manage access to their data. For example, revoking access to an email if it was sent to the wrong recipient or removing certain recipients from the access list. Of course, these features depend on comprehensive auditing and reporting of secure messages and user activity.
Preventing data breaches
The goal of email encryption is to prevent all kinds of inadvertent release of sensitive data, whether it’s because an unauthorised user gains access to the email communications channel or if an internal user accidentally emails it to the wrong recipient. The way to prevent this that works in practice as well as strategy, is to encrypt both the message itself and the communication channel, with message-level encryption and TLS. Importantly though, whatever implementation of message-level encryption an organisation uses, it needs to be easy to use and intelligent, helping the users make good decisions about securing their email data as they send it. User education is the greatest and most essential tool in the defence against a data breach.