Marquis says over 672,000 people had personal and financial data stolen in ransomware attack

Marquis, a fintech provider used by hundreds of banks, disclosed an August 2025 ransomware attack that exposed personal and financial data for at least 672,075 people — including names, dates of birth, addresses, bank account and card numbers, and Social Security numbers — and alleges attackers leveraged firewall configuration backups stolen from its vendor SonicWall to breach its network and deploy ransomware.