How does PGP (end-to-end encrypted) email work?

PGP is the benchmark for communication security. The goal of PGP is to prevent data from being read or covertly manipulated by eavesdroppers other than the sender and recipient(s). The sender encrypts the messages, but the third party has no way of decrypting them and stores them protected. The receivers obtain and decrypt the encrypted data on their own.

The encryption in canary is based on PGP key pairs. Every key pair has two keys, a public key and a secret key. To encrypt an email, the sender would require the recipient’s public key. The recipient would use their Secret key to decrypt the message the sender sent them. Similarly, to receive encrypted emails, you would have to share your public key. This public key, which you share, will be used by others to send you encrypted emails. The encrypted emails in turn would only be decrypted by your secret key. As the name suggests, secret keys should never be shared and stay with their owner, whereas the public key is shared with people who wish to send encrypted emails to you.

For more info on how PGP works, you can read the CanaryMail guide to end-to-end encryption.

How can I use PGP for my emails?

The easiest way to encrypt your emails with PGP is using Canary Mail. Canary Mail offers provider-independent support for PGP on iOS, macOS, Android and Windows.

Canary supports standard PGP that is compatible with all leading tools, apps, and services that support PGP, such as GPGTools, ProtonMail, Tutanota, K-9 Mail, Enigmail, Posteo, etc. Canary’s key search is tied into SKS, Keybase, & ProtonMail keyservers.

With Canary you can create new PGP keys right on your device, as well as use and manage all your existing encryption keys. Secret keys are stored securely in encrypted form on your device, and are never sent to the server. You can choose to save your key passphrase on the device for a limited time, or enter it as needed. In addition, Canary allows you to secure the app with FaceID or TouchID.

Canary uses the open source Bouncy Castle encryption library, which supports all modern encryption algorithms.

What are public keys and private keys?

PGP (end-to-end encryption begins by employing symmetric encryption to generate a random session key. This key is exclusive and is used to encrypt the email’s contents. Then the session key is encrypted with the recipient’s public key and transmitted along with the encrypted email to the recipient. The recipient uses his/her private key to decrypt the session key which in turn can then be employed to decrypt the encrypted email.

Can PGP encrypted emails be hacked?

While emails sent using PGP are far more secure than emails sent with TLS, no email can be claimed to be “unhackable.” 

If you use the same password for multiple services, it’s likely that your password will be disclosed if one of them suffers a security breach. If you use a strong and unique password for every account and device, you can rest certain that even if one password is compromised, the rest of your online accounts will be safe. End-to-end email encryption is most effective when used along with other internet privacy safeguards such as using a VPN to hide your browser activities and enabling two-factor authentication wherever feasible, as well as using strong passwords.

Is PGP encryption HIPAA compliant?

Yes, TLS encryption doesn’t quite make your email HIPAA compliant on its own. TLS can fail, leaving your personal information vulnerable to eavesdroppers. As a result, Pretty Good Privacy (PGP) data encryption is the most prevalent method of encrypting HIPAA compliant messages.

Where can I obtain PGP?

The easiest way to obtain PGP is using Canary Mail. Canary Mail offers provider-independent support for PGP on iOS, macOS, Android and Windows.

How secure is PGP encryption?

PGP encryption has the advantage of being virtually indestructible. Because of this, media and activists still use it and is frequently thought to be the ideal method for enhancing cybersecurity. In summary, breaking PGP encryption is practically hard for anyone, even cybercriminals and the NSA.

What if I forget my passphrase?

Unfortunately, PGP does not have a “recover my password” option. If you can’t figure it out, your only remaining option is to generate new keys. You can follow the below mentioned steps:

  1. Identify where the public key is available.
  2. Create a revocation certificate for the keys.
  3. Generate new key pair
  4. Generate revocation certificate
  5. Export private key
  6. Save both private key & revocation certificate
  7. Upload again my new public key to public keyserver

How do I choose a passphrase?

A secure passphrase is the next generation in passwords that consists of several phrases that may create a sentence as well as other sequences of words in a particular context that are simple for the user to remember. 

Passphrases tend to be longer in comparison to passwords, which makes them more secure. The most important thing here is length and not complexity. 

Avoid using a password that is simple for someone else to decipher; i.e., your favorite quotation. Additionally, refrain from using frequent phrases seen in children’s literature and hit song lyrics.

If my secret key ring is stolen, can my messages be read?

No, not until your secret passphrase has also been hacked or if an exhaustive search attack can be used to crack your passphrase. Without the other, neither is valuable. Nevertheless, you must deactivate that key and create a new key pair with a new passphrase. You might want to add a new user ID with the information of your new key ID before deactivating your old key so that others are aware of your change of address.

How do I remember my passphrase?

This may be a real issue, especially if you need to use a couple of dozen passwords on a daily basis. The entire point of passphrases would be compromised if you had to write them down somewhere so you could remember them. Unfortunately, there is no viable way to avoid this. Either you can recall it, or you can write it down and run the danger of having it compromised.