new kind of spoof: I need Help, I never saw a header like this

[TangeloIT]

Hi, one email was changed in roundcube. and the full header appears like this, anyone knows what the uk 0898 or the uploaded is? this emails was not sent or received by any server.

uk:0898
_UPLOADED_: YES
From: "envio@cliente.cnt.br" <envio@cliente.cnt.br>
Subject: Fwd: Financeiro: Boleto honorarios mes 06/2022
To: cliente@outrocliente.com.br
Content-Type: multipart/mixed; charset=utf-8; boundary="z18J=_NIKaFziUmQE3FWJUOdBXJEAoB59Q"
MIME-Version: 1.0
Reply-To: envio@cliente.cnt.br
Date: Fri, 8 Jul 2022 17:03:16 -0300

This is a multi-part message in MIME format

--z18J=_NIKaFziUmQE3FWJUOdBXJEAoB59Q
Content-Type: text/html
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline



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