- Aesto Health reported a December 2025 cyberattack breaching AWS infrastructure, affecting 9.5M patients
- Stolen data includes PII, SSNs, medical histories, billing, and insurance information across 20+ clients
- No dark web leaks confirmed; credit monitoring offered, marking 2nd‑largest healthcare breach of 2026
American healthcare technology company Aesto Health suffered the “second-largest confirmed healthcare data breach” of the year so far, having lost data on more than 9.5 million patients.