US mortgage giant Mr. Cooper on Sunday announced that customer data was compromised in an October 31 cyberattack that led to service disruptions.

As part of the attack, hackers gained access to certain Mr. Cooper systems that the company promptly shut down. This, however, also prevented the company from processing customer payments.

The company has since restored its automated phone systems and website, which enables users to access their accounts, but has yet to fully restore its operations.

In a November 12 incident notification update, Mr. Cooper also informs customers that its investigation into the attack has revealed that customer data was compromised.

“As part of our ongoing investigation, we now believe that certain customer data was exposed. We are continuing to investigate precisely what information was exposed. In the coming weeks, we will mail notices to any affected customer and provide them with complimentary credit monitoring services,” the notification reads.

While it does not say what type of information was exposed, Mr. Cooper advises customers to monitor their financial accounts and credit reports for suspicious activity and to contact major credit bureaus to warn them of potential fraud attempts.

This suggests that personally identifiable information (PII), including Social Security numbers, was likely compromised during the attack. User account details might have been exposed as well.

“Additionally, you should update your passwords frequently and with increasing complexity, and be mindful to not use the same password across multiple personal accounts,” Mr. Cooper notes.

The company underlines that the incident will not affect loan terms and that rates and fees will not be impacted. Customers will not incur late fees or penalties due to the attack, Mr. Cooper also says.

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