curl -s -u "username:password" -H "accept: application/json" -F "attachment=@file_path" -X PUT https://example.com/MailManagement/ws/v3/send/message/attachment

<cffunction name="uploadAttachment" access="remote" description="Upload An Attachment">
    <cfhttp url = "https://example.com/MailManagement/ws/v3/send/message/attachment" method="put" result="httpResp" username="username" password="password">
        <cfhttpparam type="header" name="Content-Type" value="multipart/form-data">
        <cfhttpparam type="file" file="C:temp1.txt" name="1.txt">
    </cfhttp>
    <cfset response_message = "#httpResp.tostring()#">
    <cfreturn response_message>
</cffunction>

HttpResponse<JsonNode> response = Unirest.put("https://example.com/MailManagement/ws/v3/send/message/attachment")
              .header("accept", "application/json")
              .basicAuth("username", "password") // provide Direct address and password
              .field("attachment", new File("")) // provide file to upload
              .asJson();
JsonNode json = response.getBody(); // json response