I got a message claiming to be from observium-request@observium.org with a subject starting with the word CONFIRM, then a long hex number. Body begins:
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Your membership in the mailing list observium has been disabled due to
excessive bounces The last bounce received from you was dated
11-Nov-2016.  You will not get any more messages from this list until
you re-enable your membership.  You will receive 3 more reminders like
this before your membership in the list is deleted.

To re-enable your membership, you can simply respond to this message
(leaving the Subject: line intact), or visit the confirmation page at
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Is this a legit message or is there some phishing going on?