Mid–April 2026 reporting described extortion activity attributed to ShinyHunters against McGraw Hill, with journalists citing figures on the order of ~13 million unique email addresses and analyses of a large compressed dump. McGraw Hill publicly distinguished the incident from wholesale compromise of its core Salesforce customer databases and student information systems.
Canonical record: McGraw Hill 2026 on BreachHistory.
Sources: The Register, BleepingComputer