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

Marquis, a technology company used by hundreds of banks to analyze and visualize their customer data, says hundreds of thousands of people had their sensitive personal and financial information stolen in a ransomware attack last year.

The Plano, Texas-based financial technology company is notifying at least 672,075 people that hackers stole their information during the August 2025 cyberattack, according to a list

More than half of all those affected live in Texas, according to a separate data breach notice filed in the state.

The disclosure is the most complete picture yet of the number of people affected by the breach, which has not been previously reported.

The breach allowed hackers to steal the names, dates of birth and postal addresses of bank customers. The hackers also stole customers’ financial information, such as bank accounts and debit and credit card numbers. Marquis said the hackers also took customers’ Social Security numbers.

The fintech company in February, accusing the company of security flaws that allowed hackers to steal critical information about its firewalls, which the hackers then used to compromise Marquis’ network, steal data and deploy ransomware.

In its lawsuit, Marquis said SonicWall created a vulnerability that allowed hackers to steal its customers’ firewall configuration backup files, including Marquis’ own.

Marquis did not immediately comment when contacted by TechCrunch.