[tor-bugs] #19914 [Internal Services/Service - lists]: DKIM causing trouble with Tor lists, should be stripped

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#19914: DKIM causing trouble with Tor lists, should be stripped
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     Reporter:  starlight                          |      Owner:  qbi
         Type:  defect                             |     Status:  new
     Priority:  Medium                             |  Milestone:
    Component:  Internal Services/Service - lists  |    Version:
     Severity:  Normal                             |   Keywords:
Actual Points:                                     |  Parent ID:
       Points:                                     |   Reviewer:
      Sponsor:                                     |
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 Tor Project list server does not remove DKIM headers and reliably modifies
 the Subject: header in such a manner as to produce DKIM validation
 failures.  Beyond adding a prefix which can be anticipated by
 conscientious senders, spaces are injected  at unpredictable offsets.
 This badly degrades spam-scoring of messages by Google and other ESPs and
 frequently results in the sending of list messages to spam folders.

 My recommendation is that the list server configuration be set to
 completely strip DKIM headers from forwarded messages.

 Possibly if the list server software supports it, a DKIM-signed RFC-7001
 Authentication-Results: header might be added though it seems to me the
 positive effect on spam scoring would be minor, where in comparison not
 stripping DKIM headers results in a substantial negative impact.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/19914>
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