"We become the SIM card. We can do anything the normal phone users can do," Nohl said in a phone interview.
"If you have a MasterCard number or PayPal data on the phone, we get that too," if it is stored on the SIM, he said.
The newly identified attack method only grants access to data stored on the SIM, which means payment applications that store their secrets outside of the SIM card are not vulnerable to this particular hacking approach.
Yet Nohl warned that when data is stored outside of a SIM card it could fall victim to a large range of other already known vulnerabilities, which is what has prompted the industry to put payment information on SIMs in the first place.
IPHONE, ANDROID, BLACKBERRY
The mobile industry has spent several decades defining common identification and security standards for SIMs to protect data for mobile payment systems and credit card numbers. SIMs are also capable of running apps.
Nohl said Security Research Labs found mobile operators in many countries whose phones were vulnerable, but declined to identify them. He said mobile phone users in Africa could be among the most vulnerable because banking is widely done via mobile payment systems with credentials stored on SIMs.
All types of phones are vulnerable, including iPhones from Apple, phones that run Google's Android software and BlackBerry smartphones, he said.
BlackBerry's director of security response and threat analysis, Adrian Stone, said in a statement that his company proposed new SIM card standards last year to protect against the types of attacks described by Nohl, which the GSMA has adopted and advised members to implement.
Apple and Google declined comment.
CTIA, a US mobile industry trade group based in Washington, D.C., said the new research likely posed no immediate threat.
"We understand the vulnerability and are working on it," said CTIA Vice President John Marinho. "This is not what hackers are focused on. This does not seem to be something they are exploiting."
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