Hardware appliances used by broadcasters to transmit emergency communications contained vulnerabilities that could be exploited over the Internet, although patches are now available.

The appliances from Digital Alert Systems, which is a division of Monroe Electronics, are a crucial component of the Emergency Alert System, a national program intended to disseminate public safety information over broadcast outlets within about 10 minutes.

Monroe Electronics issued a firmware update 2.0-2 for its DASDEC products on April 24, which the company said fixed several security problems.

The most serious vulnerability in DASDEC could allow an attacker to login remotely since the systems shared a root SSH key. In that scenario, an attacker could take over the system and issue emergency messages.

The vulnerabilities came to wider attention following recent advisories by the U.S. Computer Emergency Readiness Team, the Industrial Control Systems Cyber Emergency Response Team and vendor IOActive, which found the problems.

IOActive issued a news release on Monday. Gunter Ollman, IOActive’s CTO, said in an email that the company held off releasing information on the problems even though Monroe Systems had released its advisory in April.

IOActive was advised that it could take a while for companies using the equipment to apply patches, and there was a risk that malicious actors may try and exploit the issues, he said.

In February, Emergency Alert System equipment belonging to broadcasters in Michigan, New Mexico and Montana was hacked.

One of the fake messages warned “that the bodies of the dead are rising from their graves and attacking the living.”