* Group cites "credible intelligence" of possible attack
* JPMorgan Chase is second U.S. bank in two days with issues
* Bank of America problems followed threat on Internet
* Comes in wake of FBI warning on cyber attacks
By Jim Finkle and David Henry
Sept 19 (Reuters) - A financial services industry group warned U.S. banks, brokerages and insurers on Wednesday to be on heightened alert for cyber attacks after Bank of America and JPMorgan Chase experienced unexplained outages on their public websites.
The Financial Services Information Sharing and Analysis Center, which is widely known as FS-ISAC, raised the cyber threat level to "high" from "elevated" in an advisory to members, citing "recent credible intelligence regarding the potential" for cyber attacks as its reason for the move.
The problems with the websites at the two banks came after an unidentified person posted a statement on the Internet threatening to attack Bank of America and the New York Stock Exchange as a "first step" in a campaign against U.S. companies. The posting said the attacks would continue until the film that had stirred up anti-U.S. protests across the Middle East was "erased" from the Internet.
It was not possible to identify the person who posted the statement. Nor was it clear if the threat had anything to do with the issues at either of the two banks.
Dan Holden, director of security research at Arbor Networks, said that several U.S. banks were under assault by a distributed denial of service (DDoS) campaign. He declined to identify them by name.
An outside security contractor who was familiar with the attacks said that they were "massive" in scope.
Denial-of-service attacks seek to disrupt websites and other computer systems at the targeted organization by overwhelming their networks with computer traffic.
The move by FS-ISAC came just two days the FBI published a "fraud alert" advising financial services firms that cyber criminals may be disrupting service to their websites in a bid to keep banks from noticing a recent surge in fraudulent large-sized wire transfers. ()
"Often these DDoS attacks are part of a more sophisticated blended threat - One that utilizes DDoS as a diversion for more complex, difficult to detect techniques with the intention to extract customer data or financial information," said Holden of Arbor Networks.
An FBI spokeswoman declined to say if the tactics cited in the fraud alert were related to the problems experienced by the two banks.
On Wednesday the consumer banking website of JPMorgan Chase & Co was intermittently unavailable to some customers. The problems followed issues with the website of Bank of America Corp on Tuesday amid threats on the Internet that a group was planning to launch cyber attacks on a U.S. bank.
JPMorgan Chase spokesman Patrick Linehan said: "We're experiencing intermittent issues with Chase.com. We apologize for any inconvenience and are working to restore full connectivity."
A Bank of America spokesman reported no continuing problems on Wednesday. "Our online banking services have been, and are, up and running," Mark Pipitone said. "The vast majority of our customers have not experienced any issues."
'ENSURE CONSTANT DILIGENCE'
The short advisory from the industry group urged banks and other industry members to "ensure constant diligence in monitoring and quick response to any malicious events."
The Reston, Virginia-based group is owned by dozens of firms, including the two banks, as well as Citigroup Inc, Goldman Sachs Group Inc and Morgan Stanley. Insurers including American International Group, Allstate Corp and State Farm Insurance also belong to the group, as do credit card companies MasterCard Inc and Visa Inc.
The advisory also cited a warning from Microsoft Corp that hackers have attacked some of its customers by means of a security bug in its widely used Internet Explorer browser.
Microsoft has yet to release software to fix that security flaw. The German government advised the public to stop using Internet Explorer until an update is released. The U.S. Department of Homeland Security has advised users to follow steps recommended by Microsoft to reduce the risk of attacks but noted that those measures may not fully secure the browser.
The warning from FS-ISAC comes as the Obama Administration is considering issuing an executive order that could instruct government agencies to take action to help better protect the nation's critical infrastructure from cyber attacks.
Legislation that would strengthen the government's ability to help secure private networks has so far been stalled in Congress by groups concerned about privacy issues as well as business groups that oppose increased regulation of their activities.
Senator Jay Rockefeller, who heads the Senate Commerce Committee, on Wednesday sent letters to the 500 biggest U.S. companies, challenging them to improve their computer security. He blamed the defeat of the legislation on concerns raised by "a handful of business lobbying groups and trade associations."
He asked the companies to identify their own best practices and to spell out their concerns about government-conducted risk assessments that were part of the cyber security bill. He warned that the companies could face "reactive and overly prescriptive legislation" if nothing were done until some cyber disaster.
During a speech to the annual Air Force Association conference, Deputy Defense Secretary Ashton Carter complained that businesses are not doing enough to protect their own networks, saying he was disappointed that the legislation has not passed Congress.
Officials with FS-ISAC could not be reached to comment on the decision to raise its cyber threat level. A spokesman for the Department of Homeland Security declined to comment on the advisory from the industry group.