With the S&P 500 index having tripled over the last 6-plus years, many analyst are worried that the market is at risk of catastrophe.

Jeremy Warner, assistant editor of The (London) Daily Telegraph, shares that concern.

"Are overvalued stock markets heading for another crash, and if so, what in the immediate future might trigger such an event?" he writes.

"There are four parallel threats," Warner argues.

1. "A messy resolution to the eurozone crisis, with Greece defaulting on its debts and tumbling out of the euro.
2. "A further abrupt reversal in bond markets.
3. "A renewed rebound in the oil price, prompted by growing geopolitical chaos in the Middle East.
4. "A hard landing in China, a still very real possibility which everyone in Europe seems to have forgotten about amid the ongoing standoff over Greece."

And what's the most likely outcome? "An American boom, which through higher rates would in turn cause capital flight from the developing world and might therefore also trigger another emerging market crisis," Warner says.

As for the last financial meltdown, now that it has been over for six years, the unethical behavior at financial institutions that helped launch the catastrophe must have been cleaned up, right?

Not so fast. A survey of financial service professionals in the United States and United Kingdom, conducted by Labaton Sucharow law firm and the University of Notre Dame, shows that plenty of problems remain.

"With findings pointing to a continued disregard for ethical engagement and alarming new tactics to silence potential whistleblowers, the industry appears to be faltering in its reform efforts," reads a statement accompanying the survey.

It found that:

• Almost 20 percent of respondents think they must engage in illegal or unethical activity to succeed.
• A total of 32 percent believe compensation structures pressure employees to compromise ethical standards or violate the law.
• A total of 27 percent don't think the industry puts clients' interests first.
• And "an astonishing 22 percent of respondents say they have observed or have first-hand knowledge of actual wrongdoing in the workplace."

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