Even after Penney reinstated its old pricing strategy in the spring, sales again fell.  The company's shares tumbled 15 percent on Wednesday after Goldman Sachs said in a research note it expects the retailer's sales to improve more slowly than expected through the end of the year. In intraday trading on Wednesday, the shares dropped to a 13-year low.  The note also raised questions about Penney's liquidity.  (Read more: JC Penney's holiday hiring plans)  "In order to safeguard against a potentially poor 4Q (fourth-quarter) holiday season, it is likely that management will look to build a bigger liquidity buffer," Goldman analyst Kristen McDuffy wrote in her note on Wednesday.  Earlier this year, Goldman arranged a $2.25 billion loan for Penney to shore up its finances.  Last month, Penney said it expected to have $1.5 billion in cash at the end of its fiscal year on Feb. 1, enough to have ample merchandise on shelves.  (Read more: JC Penney stock is getting killed after tough Goldman report)  The cost for insurance against a J.C. Penney default has shot back to near record-high levels during the last week. With about $2.6 billion in bonds outstanding, the company has a "CCC " credit rating from Standard & Poor's, reflecting a substantial risk in owning its debt.  The company's benchmark five-year credit default swap contract price surged by more than 13 percent on Wednesday, according to Markit data.  The cost to insure $10 million of Penney bonds against a default for five years now requires an upfront payment of about $2.2 million plus quarterly payments of about $300,000 for the duration of the contract.  The contract's pricing reflects a default probability of nearly 65 percent.
JC Penney CEO Ullman told investors the retailer does not see conditions for the rest of the year where it would need to raise liquidity, a source said.