MainStreet Bancshares (Nasdaq: MNSB & MNSBP), the monetary holding firm behind MainStreet Financial institution, has disclosed a knowledge breach impacting a few of its prospects.
The incident, the corporate stated in a submitting with the US Securities and Change Fee, occurred in March 2025 and impacted a third-party vendor.
The Fairfax, Virginia-based financial institution says it instantly activated its incident response plan, launched an investigation into the matter, and terminated the seller.
On April 28, the corporate decided that the personally identifiable data of roughly 4.65% of its buyer base was compromised within the knowledge breach.
“The corporate decided that its personal data expertise techniques and networks had not been compromised or affected, no unauthorized transactions had been executed, no monies had been transferred to the unknown individuals, and prospects had been in a position to proceed to execute transactions with the corporate,” MainStreet Financial institution instructed the SEC.
In a notification letter to the impacted people, a replica of which (PDF) was submitted to the Massachusetts Workplace of Shopper Affairs and Enterprise Regulation (OCABR), the corporate revealed that the incident concerned a service provider’s cost card surroundings.
The incident spanned between April 17, 2023, and April 22, 2025, and resulted in card knowledge akin to card names, numbers, and expiration dates being compromised, the notification letter reads.
The corporate additionally says that it has no proof that non-public data akin to Social Safety numbers or MainStreet Checking account numbers may need been compromised.Commercial. Scroll to proceed studying.
MainStreet Financial institution, which operates six branches in Virginia and Washington DC, in addition to round 55,000 ATMs, is advising the possibly impacted people to go to a department to obtain a brand new card, or request one to be mailed to them, in addition to to overview their account statements for any suspicious exercise.
SecurityWeek emailed MainStreet Financial institution for added particulars on the impacted prospects, the compromised vendor, and who was liable for the info breach and can replace this text if the corporate responds.
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