Attackers are already exploiting security flaws reported by Veritas Software last week in its remote backup agent to take control of computers running the software, according to the U.S. Computer Emergency Readiness Team (US-CERT). It urged users of the software, Veritas Backup Exec Remote Agent for Windows Servers, to apply a security patch issued by Veritas.
The software is used to remotely trigger backup of data on servers. It listens for commands addressed to it on TCP (Transmission Control Protocol) Port 10,000, but there is a flaw in the way it authenticates those commands. If attackers send an over-long password, the software may crash, and if the over-long password is formed in a particular way, the computer can be forced to execute code of the attackers' choice with the privileges of the local system, allowing them to take control of the computer.
Veritas notified customers of the danger on June 22, and immediately issued a patch for affected versions of the software. It said it had been notified of the flaw by security consultancy iDefense.
In the days since Veritas revealed the danger, US-CERT has seen an increase in the number of computers scanning TCP Port 10,000, which it believes are attempts to locate vulnerable systems, it said Wednesday. Code to exploit the flaw is publicly available, it said, and it has received credible reports that this code is being used to take control of systems.
US-CERT encouraged companies running the affected software to immediately apply a patches issued by Veritas, or to use a firewall to filter traffic on arriving on port 10,000 so as only to accept commands from backup servers.