S/MIME client signing certificate attached as smime.p7s

Infos:

  • Used Zammad version: 3.5.0-1602165773.71bff28e.buster
  • Used Zammad installation source: (source, package, …) Debian package
  • Operating system: Debian Buster
  • Browser + version: chrome latest

Expected behavior:

  • When Zammad receives a signed message from a (new) client with attached a smime.p7s certificate, i.e. like the ones sent out by Thunderbird, the certificate should be saved automatically and used to verify the message signature.

Actual behavior:

  • The smime.p7s certificate is not saved and not used to verify the message signature. Opening the ticket, an error is shown about processing the client’s signature. The only way to get the message signature confirmed is to manually add a .pem version of client’s certificate in the S/MIME section.

Steps to reproduce the behavior:

  • Send a signed message to Zammad with Thunderbird

Maybe I’m missing some config parameters… is there a way to let Zammad recognize and automatically save smime.p7s certificates?

Thanks.