S/MIME decryption fails if your email is in CC instead of To

Steps to reproduce

1. Have someone send an encrypted email with your email in CC instead of To

Expected behavior

Email should be decrypted if you are included in the CC header

Actual behavior

A ServiceException is thrown with the message "Failed to find a suitable S/MIME certificate for decryption" when debugging is enabled. Otherwise a "Not found" message is shown.

Mail app version

3.2.4, 3.3.0-alpha.1

Mailserver or service

Outlook

Operating system

Ubuntu 22.04

PHP engine version

PHP 8.1

Web server

Apache (supported)

Database

MySQL

Additional info

Error is thrown in SmimeService.php in the decryptDataFetch function. For a workaround, I just cloned the foreach loop and replaced $envelope->to with $envelope->cc and have it run again.

if ($decryptionResult === null){
  foreach ($envelope->cc as $recipient) {
	  /** @var Horde_Mail_Rfc822_Address $recipient  */
	  $recipientAddress = $recipient->bare_address;
	  $certs = $this->findCertificatesByEmailAddress(
		  $recipientAddress,
		  $userId,
	  );
  
	  foreach ($certs as $cert) {
		  try {
			  $decryptionResult = $this->decryptMimePartText($encryptedText, $cert);
		  } catch (ServiceException | SmimeDecryptException $e) {
			  // Certificate probably didn't match -> continue
			  // TODO: filter a real decryption error
			  // (is hard because openssl doesn't return a proper error code)
			  continue;
		  }
	  }
  }
}

Start in SmimeService.php at decryptDataFetch and trace how recipient addresses and certificates are selected from the envelope. Reproduce the CC case with an encrypted message, then verify that a recipient in the CC header can be used for decryption without changing the existing To behavior.