Justin Clark, who back in April pinged industrial control vendor RuggedCom over a backdoor that existed in control systems based on its ROS operating system, has turned up a second vulnerability in the form of a hard-coded RSA key.
The original backdoor was a simple undocumented account designed to provide admin access in case of a lost management password. When obscurity failed, the company issued a patch disabling the backdoor.
The new vulnerability, according to the ICS-CERT advisory (PDF), is so serious that systems should be isolated from the Internet. Since the RSA key for the equipment is hard-coded in the ROS, key recovery from one device allows an attacker to decrypt SSL traffic to and from RuggedCom devices.
The advisory states that operators of the company's kit should:
Minimize network exposure for all control system devices. Control system devices should not directly face the Internet; - Locate control system networks and devices behind firewalls, and isolate them from the business network; - If remote access is required, employ secure methods, such as Virtual Private Networks (VPNs), recognizing that VPN is only as secure as the connected devices.”
RuggedCom has yet to comment on the issue. ®