Marquis ransomware attack exposed personal and financial data of 672,000 bank customers

Marquis, a Plano, Texas-based fintech company that helps hundreds of banks analyze and visualize customer data, is notifying 672,075 people that hackers stole their names, dates of birth, postal addresses, bank account numbers, debit and credit card numbers, and Social Security numbers in an August 2025 ransomware attack. More than half of those affected live in Texas, according to state filings. Marquis sued its firewall provider, SonicWall in February, alleging that a SonicWall vulnerability allowed hackers to steal firewall configuration backup files, which were then used to compromise Marquis' network and deploy the ransomware.