(TNS) — The recent revelation that Russian hacking software was found on a laptop belonging to a Vermont utility raises the question: Are our systems vulnerable?

As it turns out, the findings released by U.S. intelligence officials last weekend are more benign than what was originally reported. While the laptop was infected by Russian malware, the computer was not connected to a power grid.

Still, an attack on a U.S. power grid has long been a nightmare scenario for top U.S. officials. The National Security Agency and U.S. Cyber Command chief Adm. Michael Rogers have previously warned it’s not a matter of if but when attackers target U.S. power systems.

A Tennessee Valley Authority spokesman said cybersecurity is a matter of increasing concern for the utility and one it takes very seriously. Scott Fiedler said he “couldn’t give away the playbook,” but acknowledged TVA uses a multitiered approach to cyber security measures.

“As the nation’s largest power provider, we work around the clock to monitor our network to protect it from cyber threats,” he said. “… We perform continuous monitoring, penetration testing and vulnerability assessments.”