Mon Health says it became aware of the intrusion on July 28, when a vendor notified it of a payment that had not come through. An investigation launched into the matter revealed that adversaries likely had unauthorized access to the email system between May 10 and August 15, 2021.

As part of the incident, cybercriminals compromised a Mon Health contractor’s email account and used it to send messages in an attempt to obtain funds through fraudulent wire transfers.