Over 2.7 million cases involving Emotet malware, considered the world's most dangerous, have been detected globally since late last year, although its servers were earlier taken down in an international law enforcement operation, according to a U.S. information security firm.

Emotet, which infects computers after being sent through email attachments, has been spreading rapidly in recent months, with 90,000 cases confirmed in November and 1.07 million in January. Over 1.25 million cases were detected in early February, Proofpoint Inc. said.

Cybersecurity experts suspect a group of hackers who were not caught in the global crackdown in January 2021 started distributing Emotet toward the end of last year.

File photo shows a danger sign seen behind numbers using a laptop in Ankara, Turkey in March 2019. (Anadolu Agency/Getty/Kyodo)  

In Japan, over 20 companies and organizations, including household products maker Lion Corp. and home builder Sekisui House Ltd., are believed to have been hit by the malware.

The experts warned that the malware, which first appeared in 2014, can steal sensitive information. It is often delivered through emails disguised as reply messages from clients and friends.

About 19 million cases of Emotet infections were detected globally in one month in 2018.

Authorities in six European countries as well as Canada and the United States took down the main servers in January last year in an operation coordinated by Europol and the malware was neutralized in April.

Lion said on Feb. 3 that a computer of a group employee was infected with Emotet. The company said that data including email addresses and subject lines were stolen from its server, leading to several emails disguised as those from Lion employees being sent to multiple people.

Sekisui House said in late January that some of its computers had been infected by the malware.

Other Japanese companies and organizations that have likely been hit by Emotet include Kracie Holdings Ltd., lingerie maker Wacoal Corp., Ricoh Leasing Co. and a swimming pool operator in Wakayama Prefecture, western Japan.

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