Investors this week latched onto hope that the resignation of top brass from Petrobras will lead it out of a tangle of fundamental credibility and financial concerns that have afflicted the Brazilian company. But the oil giant's problems may be far from over.
The state-backed oil company, formally known as Petroleo Brasileiro Petrobras, said that its CEO and five other executives on Wednesday. Early rumors of the move sent its Sao Paolo-listed shares about 15 percent higher on Tuesday, and the U.S.-listed shares were more than one percent higher on Wednesday in New York.
The leadership shakeup increases the likelihood that the company will finally hand over tardy quarterly financial data that its creditors want, said Andrew Hofer, managing director of taxable fixed income at Brown Brothers Harriman.
However, the changes won't fix Petrobras' most fundamental issue in the near term: a mountain of debt coupled with low oil prices.
"The real issue with Petrobras is can it make money at the current oil price, and will the government let it make money in the refining operation," Hofer said.
Read MoreCheap oil is just one worry for Brazil's Petrobras
Petrobras did not return CNBC's request to comment.
The company, a key Brazilian economic component and among the 10 largest energy companies in the world, continues to face an investigation into alleged, huge-scale government kickbacks. Various ratings on its at least $170 billion in debt have been downgraded multiple times as crude oil prices halved in the last year.
"Brazil's new government needs the Petrobras scandal like it needs a hole in the head. This couldn't be happening at a worse time from a political and economic standpoint," Nicholas Spiro, managing director of Spiro Sovereign Strategy, told CNBC last month.
In its most recent Petrobras downgrade late last month, Moody's cited "concerns about corruption investigations and liquidity pressures that might result from delays in delivering audited financial statements." Leadership changes could help appease those concerns, including potential creditor demands to accelerate payment, Hofer said.
Read MorePetrobras surges on report Rousseff to replace CEO
Shuffling executives could lead to more consensus on what audited financial information to release and when, which could lead to a better relationship with creditors. But changing leadership was an obvious move because "no government arm ever gets terminated; you just change the people," Hofer said.
Any positive signs still don't cancel out the "more important" oil price problem, he noted. Brent crude showed signs of mounting a rally in recent trading sessions, but faltered again into Wednesday afternoon, dropping about 6 percent to sit around $54 a barrel.