PHILADELPHIA (WHDH) – Comcast is telling customers to change their passwords after hundreds of thousands of usernames and passwords appeared online, according to the Washington Post.

The Dark Web, a series of websites unavailable on search engines, turned up a post from a user who claimed to have 590,000 user accounts. To prove the legitimacy, the user released several dozen of the usernames and addresses.

Comcast says of the 590,000 usernames and passwords, only about one-third, or 200,000, were up-to-date.

A spokesman from Comcast told the Washington Post that the company is working on fixing the issue for the customers that were affected. The company says it was not hacked but rather the users had their information stolen through malware on their computers.

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