Critical flaw found in software used by many industrial control systems

IDG News Service - CoDeSys, a piece of software running on industrial control systems (ICS) from over 200 vendors contains a vulnerability that allows potential attackers to execute sensitive commands on the vulnerable devices without the need for authentication, according to a report from security consultancy Digital Bond.

The vulnerability was discovered by former Digital Bond researcher Reid Wightman as part of Project Basecamp, an ICS security research initiative launched by Digital Bond last year.

Described as a design issue, the vulnerability is located in the CoDeSys runtime, an application that runs on programmable logic controller (PLC) devices. PLCs are digital computers that control and automate electromechanical processes in power plants, oil and gas refineries, factories and other industrial or military facilities.

The CoDeSys runtime allows PLCs to load and execute so-called ladder logic files that were created using the CoDeSys development toolkit on a regular computer. These files contain instructions that affect the processes controlled by the PLCs.

According to the Digital Bond report, the CoDeSys runtime opens a TCP (Transmission Control Protocol) listening service that provides access to a command-line interface without the need for authentication.

The company has created and released two Python scripts: one that can be used to access the command line interface and one that can read or write files on a PLC running the CoDeSys runtime. There are plans to convert these scripts into modules for Metasploit, a popular penetration testing framework.

Depending on the PLC model, the command-line interface allows a potential attacker to start, stop and reset PLC programs; dump the PLC memory; get information about the tasks and programs running on the PLC; copy, rename, delete files on the PLC filesystem; set or delete online access passwords and more.

CoDeSys is developed by a company called 3S-Smart Software Solutions based in Kempten, Germany. According to the company's website, the software is used in automation hardware from over 200 vendors.

The vulnerability and scripts were tested on only a handful of products from the 261 potentially affected vendors, Digital Bond founder and CEO Dale Peterson said Thursday in a blog post. One of those PLCs was running Linux on an x86 processor while another was running Windows CE on an ARM processor.

"This attack can be used not only to control the PLC but also to turn the PLC into an 'agent' to attack other devices in the network," Ruben Santamarta, a security researcher from security firm IOActive, said Friday via email. Santamarta found vulnerabilities in industrial control systems in the past as part of Project Basecamp.

"We are aware of this security issue," Edwin Schwellinger, support manager at 3S-Smart Software, said Friday via email. "A patch is under development but not released. We are working with high pressure on these issues."