CipherMail Gateway 6.4.0 released

General
1

Today we are releasing CipherMail Email Encryption Gateway 6.4.0.

Highlights

Elliptic curve S/MIME (ECDH / ECDSA)
The gateway can now verify, decrypt, sign and encrypt S/MIME messages with EC keys, as the German
edi@energy standard (BSI TR-03116-4) requires:

  • ECDSA signatures with SHA-256/384/512
  • ECDH key agreement (standard and cofactor, X9.63 KDF, AES key wrap, RFC 5753), with CBC and GCM
  • NIST P-256, P-384, P-521 and Brainpool P-256, P-384, P-512
  • New recipient settings smime-key-agreement-scheme, smime-key-agreement-ukm and
    smime-ecdsa-signing-algorithm. The existing settings keep their meaning for RSA, so enabling EC
    never changes what is used for RSA certificates
  • RSA and EC can be disabled separately for encryption (smime-rsa-encryption-enabled,
    smime-ec-encryption-enabled) and for signing (smime-rsa-signing-enabled, smime-ec-signing-enabled)
  • The built-in CA can generate EC keys (ca-key-algorithm)

Two-factor authentication and sessions

  • A 2FA code can be used only once, only the previous, current and next codes are accepted, and a user
    is blocked after 20 failures per day (configurable)
  • Changing or disabling 2FA first asks for the current code
  • Changing the password or 2FA, disabling a portal login or deleting an admin ends the user’s other
    sessions, on every node of a cluster
  • New CLI commands auth portal 2fa reset-failures and auth admin 2fa reset-failures lift a 2FA block
  • With OpenID Connect, the identity provider handles multi-factor authentication

Webmail

  • Encrypted webmail storage now uses AES-128-GCM in AuthEnvelopedData (RFC 5083) and RSAES-OAEP with
    SHA-256, which standard tools such as OpenSSL can decrypt
  • Webmail can be decrypted with a private key on an HSM

Performance and fixes

  • S/MIME signing and encrypting of large messages uses much less heap; content over 1 MB spills to a
    temporary file
  • Messages larger than 100 MB are now DKIM signed
  • The real subject of a PGP/MIME message with protected headers (RFC 9788) is shown after decryption

Read this before upgrading

  • A portal or company portal password set on a domain or globally is now ignored. Users who relied
    on it get an invite link (with auto-invite enabled), or they can use the password reset.
  • The CLI no longer supports 2FA. ciphermail-cli on the gateway itself is not affected. An admin
    with 2FA should use the admin Shell in the web UI.
  • Portal back-end on a separate server: upgrade the portal back-end before the gateway.
  • Check ca-key-algorithm after the upgrade. ca-key-length is not migrated, so an installation
    that had raised it now issues RSA 3072 certificates until you set the new setting.
  • Webmail stored after the upgrade cannot be read after a downgrade. During a rolling cluster
    upgrade, webmail replicated to a node that has not been upgraded yet stays unreadable there until
    that node is upgraded.
  • With an HSM, set ciphermail_portal_backend__webmail_keystore_aliases to the aliases of the
    webmail keys.
  • An S/MIME message that arrives as the only attachment of a message is now delivered as an attached
    message, not unwrapped.
  • Make sure the temporary directory has room for large messages.
  • The REST endpoints for changing 2FA have changed (see the release notes).

Full release notes: Email Encryption Gateway release notes - CipherMail Email Encryption