Marquis Software Solutions Discloses Ransomware Breach Affecting 672,000 Individuals
Fintech firm Marquis Software Solutions disclosed a ransomware attack that occurred in August 2025, leading to the theft of sensitive personal and financial data, including Social Security numbers and account details. The breach impacted approximately 672,000 individuals across multiple banks and credit unions and was linked to a SonicWall firewall vulnerability.
Signal context
First seen: Mar 18, 2026
Last updated: Jun 26, 2026
Status: Public signal
Key points
- Ransomware attack on fintech firm Marquis Software Solutions.
- Breach occurred in August 2025, disclosed March 18, 2026.
- 672,075 individuals affected.
Signal analysis
BetaThis analysis groups the signal by industry, likely incident action and impacted security area. It helps compare this signal with other published signals without treating the labels as final determinations.
Sector: Information
Likely country: Location not provided
Watch ransomware, endpoint compromise and business interruption exposure.
- Source type: outside the affected organization
Impact area: Confidentiality, Availability
Likely asset: User or customer data
- 26 signals in the same sector
- 100 signals with the same likely impact area
- 1 signal linked to this organization/domain
External sources
The incident, which occurred in late January 2026, involved the compromise of protected health informationhttps://blackfog.com/the-state-of-ransomware-march-2026/Public source from blackfog.com.
The Worst Data Breaches of March 2026 | Strobeshttps://strobes.co/blog/worst-data-breaches-march-2026/Public source from strobes.co.
Marquis Fintech Ransomware Breach: 672000 Victims Who Never Heard of the Company That Lost Their Datahttps://breached.company/marquis-fintech-ransomware-breach-672000-victims/Public source from breached.company.
Data Breach Roundup (Mar 13-19, 2026) - Privacy Guideshttps://www.privacyguides.org/news/2026/03/20/data-breach-roundup-mar-13-19-2026/Public source from privacyguides.org.
Marquis: Ransomware gang stole data of 672K people in cyberattack - Bleeping Computerhttps://www.bleepingcomputer.com/news/security/marquis-ransomware-gang-stole-data-of-672-000-people-in-2025-cyberattack/Public source from bleepingcomputer.com.
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