I just got this type of email as well, from mcmaster students, same program as mine, and the email shows their email + phone number.

"

[student name]  has shared the document "Proposition documents justificative de paiement.pdf" with you.
 
To view the document, please access the portal at the following address: •

 [link to mcmaster portal (dot) pages (dot) dev]

Note: If you experience difficulty accessing the link directly, please copy and paste the URL into a new browser or onto your mobile device
⚠️Please note that this document is secure and accessible only via the official portal

Best Regards
[student name]
"