Ally Bank is the latest financial institution to come under cyberattack from unknown hackers.
A company spokesperson told Reuters that the attack had not yet led to disruptions for customers.
A number of banks — including PNV, BB&T and Capital One have faced similar attacks in recent weeks. Yesterday HSBC was attacked in what security experts call a DDOS (distributed denial of service) action, in which hackers overwhelm a company’s servers with millions of connection requests.
An Islamist group has claimed responsibility for the attacks. Reuters reports that the DDOS actions may be part of a large-scale, prolonged effort.
Sources have previously told Reuters that the attacks could be part of a year-long cyber campaign waged by Iranian hackers against major U.S. financial institutions and other corporate entities.
While banks have stressed that customer accounts and information has not been at risk, the attacks have highlighted the growing threat from hackers against U.S. infrastructure. Last week, U.S. Defense Secretary Leon Panetta urged Congress and businesses to step up cybersecurity efforts.