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Jeff Fusco—AP Images for Comcast

If you're a Comcast subscriber who uses the email account that comes with your Internet service, you may have received an email from Comcast prompting you to reset your password.

Recently a large database of customer information-- some 590,000 accounts and passwords--was found for sale on the dark web, according to CSO. The dark web refers to networks not normally accessible to the public, and hackers regularly use these networks as marketplaces for their services. As for the price for the information, it was set at only $1,000 for the lot.

Comcast cross-referenced many of the accounts and found that around 200,000 were still active. It immediately reset them, and alerted customers that they'd need to reset their passwords.

It's unclear how the hack happened, but since around 60% of the accounts were inactive it's likely the info was old, taken from old data breeches, phishing scams, or malware.

According to the ad for the data, only one sale has been made, presumably to Comcast, so this doesn't pose a huge risk.

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