A Richmond technology firm has closed security holes in a popular system that enables corporations, government agencies and others to control millions of devices over the World Wide Web, the Department of Homeland Security said in an advisory Wednesday.

Tridium Inc. issued a “patch” for Niagara Framework, a software system used by more than 300,000 organizations in 52 countries to remotely control or monitor medical devices, elevators, furnaces, video cameras, security systems and a wide array of other equipment.

Wednesday’s advisory came one month after homeland security officials warned that Niagara was open to attack from hackers who exploited a well-known vulnerability. The department’s July 13 alert followed a Washington Post story about Niagara and holes discovered by two cybersecurity researchers contacted as part of the reporting.

The researchers, Billy Rios and Terry McCorkle, determined that hackers could, among other things, easily breach the system and download user names and passwords. They alerted DHS to their findings.

The disclosure of the vulnerabilities came amid public debate about the security of computer systems that increasingly control buildings, manufacturing, power grids and other parts of the nation’s critical infrastructure that are linked to cyberspace.

It also set off a scramble by Niagara users and resellers, scores of whom joined a new online group to exchange ideas about making the platform more secure.

In Wednesday’s advisory, official with DHS’s Industrial Control Systems Cyber Emergency Response Team said Tridium issued fixes for four different vulnerabilities. Those gaps would let a hacker gain access to restricted files, including “authentication credentials,” by sending a “specially crafted request to the Web server,” the advisory said.

“These vulnerabilities can be exploited remotely,” the team said. “An attacker with a medium skill could exploit these vulnerabilities.”

Tridium issued its own advisory in recent days, urging customers and users to “apply this patch” to current Niagara systems or to upgrade older systems and then make the security improvements.

“Tridium understands the importance of providing a securable software framework to its customers. Whenever critical security issues are discovered, Tridium is committed to taking the appropriate steps to resolve them quickly.”

A spokesman for Tridium’s parent, Honeywell, said the updates were sent to equipment makers that use Niagara, integrators and others “strongly urging them to reach out to their customer base with the security update details.”

“Ensuring the highest levels of security of the Niagara AX Framework is a top priority for Tridium, and the work we’re doing with organizations like ICS-Cert and our customers shows how seriously we take these issues,” Honeywell spokesman Bruce Eric Anderson said.

John Sublett, co-founder and Chief Technology Officer for Tridium, Inc. The company's central technology is a software framework called the Niagara Framework. This technology allows various devices and services to be controlled remotely. (Matt McClain/FOR THE WASHINGTON POST)