South Dakota Data Breaches

The City of Mitchell experienced a data breach on August 24, 2026, according to a ransomware tracker. The full extent of the breach is currently unknown.

Phase Technologies data breach in 2026 was reported on a ransomware victim listing, but the incident has not been publicly confirmed by the company or a regulator.

SBI Manufacturing data breach reporting in 2026 appears only in ransomware.live, which listed the company as an Orova victim on 2026-08-04. No official confirmation, affected count, or data type details were publicly confirmed in the sources reviewed.

Navient Corp experienced a third-party data breach in June 2026, where unauthorized access to a law firm's systems exposed the personal data of approximately 2.5 million student loan borrowers.

Sayre Associates, a civil engineering and land surveying firm, reportedly experienced a data breach in 2026, according to ransomware monitoring sites. The company has not publicly confirmed the incident.

The purported 2026 data breach at "Lee Law Offices" is a misidentification. The research indicates a major AT&T data breach affecting over 100 million individuals in 2024, which frequently causes confusion in data security discussions.

CarGurus, Inc. experienced a data breach in February 2026, reportedly compromising the data of millions of user accounts and corporate records.

Chrysler experienced a data breach in late 2025, with the Everest ransomware group claiming to have stolen over 1TB of data affecting customers nationwide.

A data incident involving Medicare.gov accounts operated by the Centers for Medicare & Medicaid Services (CMS) may have impacted approximately 103,000 Medicare beneficiaries, not Aetna, with notifications sent in 2023 or 2024.

Landmark Admin, LLC experienced a 2024 data breach affecting approximately 1.6 million people. Reported exposed information included Social Security numbers and financial information; the incident involved Landmark Admin’s administration of information for Liberty Bankers Insurance Group and Accendo Insurance Company.

Medusind, Inc. experienced a regulator-confirmed data breach on December 29, 2023, involving personal, medical, insurance, payment, and government-identification information. The number of affected individuals has not been publicly identified in the sources reviewed.