Lax lending standards were widely faulted for triggering the 2008 financial crisis. If recent developments are any indication, those conditions may be making a comeback.
In an effort to accelerate lending to lower- and middle-income borrowers, mortgage giants Fannie Mae and Freddie Mac are launching programs that will guarantee loans with down payments of as little as 3 percent.
But could an ultralow down payment create a housing market boom, or could it lead to another mortgage bubble? A prominent housing market expert who made his name predicting the 2008 bust has at least some doubts.
"It sounds a little risky," Nobel Prize-winning economist Robert Shiller told CNBC. "Risky for the lender, and for the mortgage insurer who is going to insure" the mortgage obligations, he added.