The attack, which took down some of the servicer's systems, happened Oct. 30 and compromised the Social Security numbers of 14.7 million customers, a data-breach notification filed in Maine shows.

Thus far, 13 class action lawsuits have been filed against the servicer accusing it of failing to keep its customers' personal identifiable information safe. As of Dec. 14, a motion was filed in the Northern District of Texas to consolidate all of the suits into a single case under plaintiff Jennifer Cabezas, who was the first of the 13 to bring a motion against the servicer.

Plaintiffs argue rolling all the suits into one is appropriate because it will "streamline the litigations and save both party and judicial resources."

There is also "little to no risk of prejudice or confusion from consolidation as each of the plaintiffs consented to this motion, and their counsel are collectively and cooperatively working together and agree consolidation is in the best interest of plaintiffs," court documents said.

Pending litigation against the servicer accuses it of failing to secure and safeguard customer data and not being transparent in communicating with customers. None of the 13 suits have been officially certified as class actions.

Mr. Cooper did not immediately respond to a request for comment.

In early December, the servicer announced it would compensate current and former borrowers for the breach by footing the bill for two years of complimentary identity-protection services, including credit monitoring. The services will be provided by Cyberscout through Identity Force, a TransUnion company specializing in fraud assistance and remediation services.

Notification letters will be mailed to customers containing enrollment instructions for the free identity protection services, the servicer previously stated. Mr. Cooper has also set up a call center supported by TransUnion to answer borrower questions.

Covering the cost of identity monitoring services will make a notable dent in Mr. Cooper's bottom line, pushing vendor related expenses in the fourth quarter to $25 million (from $5 to $10 million), per a company filing with the Securities and Exchange Commission in early December.