A discontinued model of Nokia mobile phone is fetching thousands of euros in the second-hand market as criminals discover the phone’s exploitable software flaw which they can use to hack into online bank accounts, an investigator from the Netherlands reports.

Investigators have already seen someone transfer €25,000 (US$32,413) for a German version of a Nokia 1100 phone, according to Frank Engelsman of Ultrascan Advanced Global Investigations. The low-priced mobile phone was targeted for sale in developing markets and initially sold for less than €100. Police had contacted them before regarding this strange price increase and asked Ultrascan if there was anything special about the phone. 

The investigators discovered that according to an informant, only Nokia 1100 phones made in a plant in Bochum, Germany were fetching these high prices as these specific models contained flawed software from 2002 which was vulnerable to hacking.

While the investigators do not know the exact details of the phone’s use in cyber crimes, informants told Ultrascan that the phones can be manipulated to intercept unique one-time passwords used in online banking transactions. Certain Moroccan, Romanian and Russian gangs have been known to obtain these Germany-made Nokia phones.

Cyber crime gangs have accumulated thousands of usernames and pass words for online bank accounts from Holland and Germany. However these banks also request transaction authentication numbers (TAN), a one-time-use password used to complete online transactions.

Before, banks gave out lists of TANs to customers, requiring them to use one for each transaction. However, successful phishing activities by unscrupulous groups have lead banks to issue TANs directly to the account owners via SMS, according to Engelsman.

These particular Nokia 1100 phones can be reprogrammed to spoof another person’s number, and criminals can use this to intercept TANs in order to use other people’s accounts to transfer money to criminal accounts. Engelsman says that Ultrascan is trying to get hold of one of these Nokia 1100 phones in order to verify this report.

The Nokia 1100 has also been used for other criminal activities. In a drug-related case, police were having problems tracking SMS sent from certain Nokia 1100 phones. A software exploit has apparently made it possible. However, the police were still able to locate the users by discovering the general area where the phones were used.