Cyber experts on Tuesday said the Indian banking system could be the next victim of the WannaCry “ransomware” cyber attack, ANI reported. The Reserve Bank of India, however, said a Windows security update could prevent and protect the institutions from any breaches.

“We are closely monitoring the situation and have instructed the banks’ local information technology teams to keep a watch on the systems in branches. In some cases, the malware comes from external devices interacting with the banking networks. We are keeping that under check too,” a State Bank of India official told The Economic Times. The English daily, however, indicated a possibility that Indian banks were under-reporting their susceptibility to the cyber crimes.

Over 60% of the 2.25 lakh ATMs in India use an outdated Windows XP, Money Control reported. A Bank of Baroda official, however, said the machines were less susceptible as they work on a closed network.

The international cyber attack was orchestrated using a malware called Wanna Decryptor or WannaCry. With this extortionist “ransomware”, hackers blocked access to files by encrypting the data, which can be decrypted only once they are paid a ransom in bitcoins.

The breach was first reported at Britain’s National Health Service. Spain’s communications giant Telefonica, utility provider Gas Natural and power firm Iberdrola were hit, as well as the Russian Interior Ministry and FedEx operations in the United States. Reports poured in from Portugal, Ukraine and Taiwan, too.

The major cyber attack had brought operations at hospitals, telecommunications firms and other companies to a halt. The Computer Emergency Response Team has suggested using patches in users’ Windows systems to prevent the bug from spreading. The ransomware also “drops a file named ‘!Please Read Me!.txt’ that contains the text explaining what has happened [to the computer] and how to pay the ransom”.