The Wiert Corner – irregular stream of stuff

A very interesting 2020 read that will remain valid eternally: [Wayback/Archive] Stop Using Encrypted Email | Latacora

It lists reasons that an encrypted email will one day leak either enough of the content or enough of the meta-data to become problematic:

• If messages can be sent in plaintext, they will be sent in plaintext: the “unencrypted reply” argument.
• Metadata is as important as content, and email leaks it.
• Every archived message will eventually leak.
• Every long term secret will eventually leak.

The last two arguments come down to the (data) hoarding nature of people and organisations.

Information security is about knowing how shortly to keep data, then ditch it.

Few people and organisations do that. All others keep things for too long, or even eternity.

Basically any party involved has to fuck up just once to leak (in other words: for eternally do things right not to leak). Adversaries only have to get it right once to obtain data.

The above gets worse when the underlying encryption software breaks, which it does. Just a few examples:

• PGP broke multiple times (it is way to complex by design)
• S/MIME had multiple security issues
• OpenPGP.js (on which a lot of tooling relies) broke multiple times
• XML Signature (XMLDSig) and other XML security solutions suffer from similar architectural problems as PGP

Most if not all of the above are implemented using static public/private key pairs that do not expire, adding to the risk of leaking over time.

The alternatives to the above schemes just ditch SMTP. Signal is a very good try, as it very well encrypts metadata as well as content data, but suffers from unsafe clients (not just TM SGNL).

Basically secure communications depends on the parties communicating and the parties in the future having access to the messages. Trusting the future historically has been a bad idea: basically it’s like Godwin’s Law.

Via

• [Wayback/Archive] Stop Using Encrypted Email with William Woodruff
• [Wayback/Archive] Stop Using Encrypted Email with William Woodruff – YouTube

Related

• [Wayback/Archive] Mailpile: Some thoughts on working with GnuPG
• [Wayback/Archive] CVE-2025-47934 – Spoofing OpenPGP.js signature verification — Codean Labs

--jeroen