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Medium

Kettering Health Hit by System-Wide Outage After Ransomware Attack

Kettering Health, a healthcare network in Ohio, experienced a ransomware attack on May 20, 2025, causing a system-wide technology outage.

Key points

  • Ransomware attack on May 20, 2025, caused a system-wide outage at Kettering Health.
  • Interlock ransomware group claimed responsibility, exfiltrating 941 GB of data.
  • Disrupted operations, including canceled procedures, phone lines, and patient portals.

Connected intelligence

Signal brief

Follow the organization, likely method and potential impact to explore connected Shadow Tier intelligence.

02

Likely method

Ransomware

Malware activity

03

Potential impact

Potential operational disruption

Confidentiality, Availability

Published
May 20, 2025
Updated
Jun 26, 2026
Confidence
Medium
Evidence
2 sources

Structured assessment

Signal analysis

This 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.

Threat source

Malware activity

Watch ransomware, endpoint compromise and business interruption exposure.

  • Source type: possible insider or internal misuse

Business impact

Potential operational disruption
Impact area
Confidentiality, Availability
Likely asset
User or customer data

Mentioned entities

KetteringhealthData DisclosureKettering Health HitKettering HealthOhioInterlockWhileThe InterlockRansomwareKettering Health. Interlock

Quick context

Questions about this signal

What happened in this signal?

Kettering Health, a healthcare network in Ohio, experienced a ransomware attack on May 20, 2025, causing a system-wide technology outage. The attack, attributed to the Interlock ransomware group, forced the cancellation of inpatient and outpatient procedures and disrupted phone lines and patient portals. While emergency rooms remained open, staff reverted to manual, pen-and-paper workflows. The Interlock group claimed to have exfiltrated 941 GB of data, including patient information, and leaked it when the ransom was not paid.

When was this signal reported?

Shadow Tier lists May 20, 2025 as the signal date.

Which organization is connected to this signal?

Ketteringhealth is the organization connected to this public signal.

Explore Ketteringhealth
Which attack pattern is relevant?

This signal is connected to current ransomware incidents based on its reported incident context.

Explore current ransomware incidents