Data Breach at Canada Post Canada's primary postal operator, Canada Post, confirmed Wednesday that it has suffered a data breach. The security incident occurred following a cyber-attack on one of the Crown corporation's suppliers, Commport Communications, which provides electronic data interchange solutions. Commport Communications was hired by the postal service to manage the shipping manifest data of its large parcel business' customers. Following the cyber-attack, Canada Post has informed 44 of its commercial customers that data belonging to more than 950,000 customers has been compromised. Commport Communications notified Canada Post that manifest data stored in its systems had been exposed in a malware attack on May 19.