5 ms·

> at rest So we're talking about after it's received and processed by a server. > Email is built on top of plain text protocols and messages flow in plain tex

> at rest So we're talking about after it's received and processed by a server. > Email is built on top of plain text protocols and messages flow in plain text. If you encrypt, you cannot scan for spam or viruses... But you can? Just scan and process before encrypting. > ...index messages for searching This indeed is a problem. Encrypting emails individually makes search difficult. Why not just encrypt entire hard drives? Encryption at rest is a very broad term. > or recover messages when a password gets lost. Not to mention the usability issues of changing passwords and encryption keys. This has nothing to do with email. This is encryption in general, and these security details are a feature. > Some other providers automatically encrypt messages as they arrive using users’ public keys. That sounds exciting but in practice that means you cannot access your messages using the webmail unless you pasted your private key into a browser, and have it handled by script and a myriad of third party code. Ouch. Huh? I haven't heard of copy-pasting private keys. Use passwords. But more importantly, this is specific to webmail, not email in general.

chongli 6y ago
But you can? Just scan and process before encrypting. You can't. End-to-end encryption for email means the messages are encrypted by the sending client and decrypted by the receiving client. The server has no chance to scan anything because it cannot decrypt the messages.
- JshWright 6y ago
  End-to-end encryption and encryption at rest are two very different things.
  - jb_gericke 6y ago
    Not clear if the author is referring specifically to mail services like gmail here. Full disk encryption would indeed encrypt my email at rest (assuming I'm syncing mail locally on my laptop with FDS turned on).
jcims 6y ago
The title is throwing off how we’re reading the article. It’s really about why they, an email provider, can’t meaningfully encrypt email at rest. FTA: >If you are interested in real encryption, please use end-to-end encryption tools such as GPG or fetch locally all your messages periodically and encrypt them yourself. I would say their standard for being ‘encrypted at rest’ is including a requirement that they are unable to open it. This is textbook ‘perfect being the enemy of the good’. There are a lot of threats outside of malicious insiders that could be deterred or slowed down by a practical encrypted storage mechanism.
- Jon_Lowtek 6y ago
  yeah that gets clear when they talk about their certified physical security: there is a strong assumption that drives can not be stolen and will be destroyed at their EOL. Such assumptions often don't hold. Encryption and physical protection are not redundant, they are defense in depth. I agree with the GPG part and that a mail provider can not reasonably create something similar, however they have a weird understanding of "encryption at rest" at the base of their argument why they don't do it.
  - PeterisP 6y ago
    In addition to protecting against losing hard drives, 'encryption at rest' (as applied in e.g. card industry) can also protect the data from an attacker who gets full access to the database through e.g. a SQL injection, if properly implemented.
- matheusmoreira 6y ago
  > please use end-to-end encryption tools such as GPG or fetch locally all your messages periodically and encrypt them yourself This is good advice but it just isn't going to happen in practice unless gmail makes it the default for everyone. WhatsApp added support for the Signal protocol and made it the default for all users, now the whole world is communicating with end-to-end encryption.
  - Jon_Lowtek 6y ago
Cantbekhan 6y ago
Couldn't the indexing issue be solved by only having the client/user do the indexing while e-mails are stored encrypted on the server? Ideally on an encrypted device which will keep/maintain the indexing. Shifting the burden of indexing e-mail (and decrypting/encrypting the at rest) on the client willing to achieve this? Edit: The webmail/imap/pop provider would only have to receive an e-mail and use a client provide public key to encrypt the mail and let it rest. The webmail client could (in browser) or through their app do the decryption/indexing locally. Could be done with an extension.

chongli 6y ago

But you can? Just scan and process before encrypting. You can't. End-to-end encryption for email means the messages are encrypted by the sending client and decrypted by the receiving client. The server has no chance to scan anything because it cannot decrypt the messages.

JshWright 6y ago
End-to-end encryption and encryption at rest are two very different things.
- jb_gericke 6y ago
  Not clear if the author is referring specifically to mail services like gmail here. Full disk encryption would indeed encrypt my email at rest (assuming I'm syncing mail locally on my laptop with FDS turned on).

jcims 6y ago

The title is throwing off how we’re reading the article. It’s really about why they, an email provider, can’t meaningfully encrypt email at rest. FTA: >If you are interested in real encryption, please use end-to-end encryption tools such as GPG or fetch locally all your messages periodically and encrypt them yourself. I would say their standard for being ‘encrypted at rest’ is including a requirement that they are unable to open it. This is textbook ‘perfect being the enemy of the good’. There are a lot of threats outside of malicious insiders that could be deterred or slowed down by a practical encrypted storage mechanism.

Jon_Lowtek 6y ago
yeah that gets clear when they talk about their certified physical security: there is a strong assumption that drives can not be stolen and will be destroyed at their EOL. Such assumptions often don't hold. Encryption and physical protection are not redundant, they are defense in depth. I agree with the GPG part and that a mail provider can not reasonably create something similar, however they have a weird understanding of "encryption at rest" at the base of their argument why they don't do it.
- PeterisP 6y ago
  In addition to protecting against losing hard drives, 'encryption at rest' (as applied in e.g. card industry) can also protect the data from an attacker who gets full access to the database through e.g. a SQL injection, if properly implemented.
matheusmoreira 6y ago
> please use end-to-end encryption tools such as GPG or fetch locally all your messages periodically and encrypt them yourself This is good advice but it just isn't going to happen in practice unless gmail makes it the default for everyone. WhatsApp added support for the Signal protocol and made it the default for all users, now the whole world is communicating with end-to-end encryption.
- Jon_Lowtek 6y ago

Cantbekhan 6y ago

Couldn't the indexing issue be solved by only having the client/user do the indexing while e-mails are stored encrypted on the server? Ideally on an encrypted device which will keep/maintain the indexing. Shifting the burden of indexing e-mail (and decrypting/encrypting the at rest) on the client willing to achieve this? Edit: The webmail/imap/pop provider would only have to receive an e-mail and use a client provide public key to encrypt the mail and let it rest. The webmail client could (in browser) or through their app do the decryption/indexing locally. Could be done with an extension.