text: Published Wed, Jul 22 20156:15 AM EDT Updated Wed, Jul 22 20158:29 AM EDT
  A huge computer attack against JPMorgan Chase last summer may have been more of an attempt to fuel an ongoing pump-and-dump stock scheme rather than an effort to steal financial data from the nation's biggest bank.
  But authorities also suspect that some of the men arrested, along with a fifth man charged but still at large, had a hand in last summer's hacking at JPMorgan that compromised the contact information for 83 million of the bank's customers, according to people briefed on the matter who spoke on the condition of anonymity.
  One of two Israeli men charged with the hacking of the JPMorgan Chase bank attends a court hearing, on July 22, 2015 in Jerusalem, Israel.
  A series of court filings unsealed by federal prosecutors in Manhattan did not mention the attack on JPMorgan's vast network that went on for several months before it was discovered in late July. Rather, the court filings detailed charges involving a multiyear campaign to drive up the price of worthless penny stocks by pitching them to unsuspecting investors through millions of spam emails.
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  In a criminal indictment, Mr. Aaron was described as a frontman for the pump-and-dump schemes who went by the alias "Mike Shields" and communicated with unidentified stock promoters in the United States at Mr. Shalon's direction. Prosecutors contend the investment schemes made millions of dollars for the men, who laundered their money through bank accounts for a Cyprus-based shell company that had no actual business.
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  Soon after the hacking was discovered at JPMorgan, agents with the Federal Bureau of Investigation determined the attack was not particularly sophisticated even though the bank's security people had argued otherwise. The hacking succeeded largely because the bank failed to properly put updates on a remote server that was part of its vast digital network.
  Preet Bharara, the United States attorney in Manhattan, said in a statement: "As alleged, the defendants manipulated trading in U.S. securities from overseas, using fake identities to funnel millions of dollars in unlawful proceeds through a web of international shell companies. Using false and misleading spam emails sent to millions of people, these defendants allegedly directed their pump-and-dump scheme from their computers halfway around the world."
  The attack on the bank was discovered somewhat by accident. In July, security employees of the bank learned that the website for the JPMorgan Corporate Challenge, a charitable race organized by the bank, had been hacked and compromised. The website is run by an outside vendor for the bank. But information gleaned from the hacking on the racing website pointed back to a bigger problem with the bank's own network.
  Federal authorities in New York had made the JPMorgan attack a priority investigation because the bank is a critical component of the nation's financial system. The hackers had tried to infiltrate nearly a dozen other financial institutions but were less successful. By the spring, some investigators were expressing confidence in private that they expected to announce some arrests by the summer if not earlier.
  Much of the JPMorgan investigation for Mr. Bharara's office was overseen by Nicole Friedlander, a chief of the online crimes division, who was working while out on maternity leave for several months, said people briefed on the matter.