A computer virus said to have been created by the US and Israel in order to spy on the Iranian uranium enrichment facilities in Natanz was found in American oil giant Chevron’s computer network, the Wall Street Journal reported late Thursday.

The paper cited Mark Koelmel, general manager of Chevron’s earth sciences department, as saying that the sophisticated virus known as Stuxnet was found in the energy firm’s systems in summer 2010, shortly after its existence was first reported in a blog.

“I don’t think the US government even realized how far [the virus] had spread,” Koelmel was quoted as saying. “I think the downside of what they did is going to be far worse than what they actually accomplished.”

Stuxnet is designed to target programmable logic controllers (PLCs), which are used to automate factory equipment and are used at many plants around the world — making many companies susceptible to infection by the virus. According to the Wall Street Journal, many PLCs — among them those used at Natanz — are manufactured by German company Siemens AG.

Nevertheless, Stuxnet caused no harm to Chevron’s network. “We make every effort to protect our data systems from those types of threats,” company spokesman Morgan Crinklaw told the Wall Street Journal.

According to the report, Chevron — the first American firm to report a Stuxnet infection — was neither infected with the virus intentionally nor through a hacking attempt.

“We’re finding it in our systems, and so are other companies,” Koelmel was quoted as saying, suggesting the virus was waiting in the wings of cyberspace to infect vulnerable firms around the world.