Hackers used a Trojan horse to break into the systems of more than 50 companies, many of them in the chemical and defense sectors, reports Computer World.

Symantec released the report Monday that revealed the attackers had been stealing the companies' secrets from late July through mid-September, according to BBC News. The security company said the attack was focused on intellectual property, including design processes and formulas.

CNET reports that targets included multiple Fortune 100 companies that conduct research and development of chemical compounds, including advanced materials for military vehicles.

The attack was allegedly created in China, according to Fox News, which also reports that 29 chemical companies were attacked along with at least 19 companies from other sectors.

Hackers used an off-the-shelf Trojan horse to steal the information, reports Reuters India. Users either received an e-mail asking them to update their security software or bogus e-mails from established business partners, which then unleashed the PoisonIvy virus that extracted information from their computers.

The attack struck servers based mostly in the United States, United Kingdom and Bangladesh, reports The Register.

According to the San Francisco Chronicle, the hackers targeted non-governmental organizations working on human rights issues from late April to early May before moving on to chemical companies.

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