More than 38% of the 2,300 mortgage complaints sent to the Consumer Financial Protection Bureau in December related to loan modification and foreclosure concerns, the largest share in this category.

The CFPB took nearly 10,000 total complaints across its entire array of monitored financial products since July, which includes payday loans, student loans, credit cards and others.

And the bureau reports that when the CFPB comes calling, mortgage firms largely answer.

The bureau said implicated companies responded to 88% of the complaints. Of these, companies provided relief — in some cases  payment to the borrower — on more than half. Nearly 19% of the relief provided went to mortgage-related complainants.

The CFPB began taking consumer complaints regarding mortgages at the beginning of that month. Of these, 889 regarded problems with mortgage modifications or the foreclosure process, nearly double the next largest category, according a semi-annual report to Congress from the bureau.

Taking the 501 complaints about making payments, escrow accounts and loan servicing, more than half of all concerns regarded the mortgage servicing industry.

Complaints about applying for a loan, an originator or broker accounted for nearly 10% of those filed, and less than 3% regarded the decision relating to a mortgage or the underwriting of a mortgage.

Also in December, the CFPB joined a task force with the Special Inspector General of the Troubled Asset Relief Program and the Treasury Department to crack down on foreclosure scams targeting Home Affordable Modification Program applicants.

CFPB Director Richard Cordray said before the Senate Banking Committee Tuesday that the bureau has begun assessing policies at “certain mortgage servicing companies.”

Senate Republicans blocked a vote on his nomination before President Obama made the recess appointment earlier this month. At the hearing, they pressed him on how he would handle the balance between enforcement, rulemaking and the safety and soundness of the financial system.

Cordray said while the bureau is dedicated to ridding the bad players and practices from the business, he would be mindful not to punish those who’ve avoided recent problems in the mortgage space.

“I think it is irresponsible to think you can protect consumers while killing off institutions,” Cordray said.

Write to Jon Prior.

Follow him on Twitter @JonAPrior.