By CBS3 Staff

PHILADELPHIA (CBS) — A warning for some Jefferson Health cancer patients: your personal information could be in the hands of hackers.

The health system says the cyberattack involves a vendor called Elekta, which handles patient information for cancer treatments.

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We’re told the hackers obtained patients’ names, dates of birth, and some medical information back in April.

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They also got some patients’ social security numbers.

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Jefferson Health is contacting everyone who is affected and will offer free credit monitoring and identity theft protection to people whose social security numbers were stolen.