In the eyes of TrimTabs, the Federal Reserve, with its massive easing program, has done more than send bond yields to record lows last year and stock prices to record highs this year.

"We think investors with a longer-term outlook should tread carefully in financial markets," the research firm said in a market analysis obtained by CNBC.

"The Federal Reserve and its fellow central banks have succeeded in making almost every major asset class in the world overpriced."

Video: Economist Predicts 'Unthinkable' for 2013

The Fed has expanded its balance sheet by more than $2 trillion over the past five years, and is now purchasing $85 billion of Treasurys and mortgage-backed securities a month.

TrimTabs cites several signs of market mania: global junk bond issuance hit a record $254 billion through May; houses are being flipped in California at their fastest pace since 2005, according to The Wall Street Journal; and investors are seeking synthetic collateralized debt obligations again.

"It is amazing how quickly bubble behaviors from the last decade have come back," notes TrimTabs CEO David Santschi.

Still, he doesn't expect an imminent tumble in stocks.

But markets may be headed for bad times before long. Pimco co-chief investment officer Bill Gross predicts the Fed will pull back on its quantitative easing by year-end.

"I have a sense at some point later in the year they will have to taper, if only because the budget deficit isn't what it was," he told Yahoo. "Depending on the number, a $600 billion deficit does not allow for $85 billion a month in check writing."

Video: Economist Predicts 'Unthinkable' for 2013