Pennsylvania healthcare provider Keystone Health has started informing patients of a data breach potentially impacting their personal information.
In a data breach notification published on its website, Keystone is disclosing a cybersecurity incident identified on August 19 and which has resulted in the disruption of some systems.
The healthcare provider says it immediately launched an investigation into the incident, which discovered that certain patient information might have been compromised.
“Our investigation found that an unauthorized party accessed files within our system between July 28, 2022 and August 19, 2022. Some of those files contained patient information, including names, Social Security numbers, and clinical information,” the data breach notice reads.
Keystone says it has already started mailing letters to the affected patients, offering them credit monitoring services.
No other information regarding the incident has been provided and it is unclear whether Keystone Health fell victim to ransomware or to a different type of cyberattack.
On Friday, Keystone notified the US Department of Health and Human Services that over 235,000 individuals were impacted by the incident.
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