Defect #38514
Updated by Holger Just 12 months ago
Registration email from redmine.org triggers the following rspamd symbol:
<code>
Symbol: HFILTER_HELO_5(3.00)
</code>
From the headers:
<code>
Received: from static.126.101.4.46.clients.your-server.de ([46.4.101.126]:43352 helo=Ubuntu-2004-focal-64-minimal)
</code>
I think this HELO Ubuntu-2004-focal-64-minimal is what rspamd takes offense at. It should probably be a FQDN.
But TBH I was not able to figure out what exactly the rspamd symbol meant quickly so this might be wrong.
See https://www.rfc-editor.org/rfc/rfc5321.html#section-4.1.1.1 which says
<pre>
These commands are used to identify the SMTP client to the SMTP
server. The argument clause contains the fully-qualified domain name
of the SMTP client, if one is available. In situations in which the
SMTP client system does not have a meaningful domain name (e.g., when
its address is dynamically allocated and no reverse mapping record is
available), the client SHOULD send an address literal (see
Section 4.1.3).
</pre>