Rockwell ThinManager Vulnerabilities Could Expose Industrial HMIs to Attacks

Vulnerabilities discovered by researchers in Rockwell Automation’s ThinManager ThinServer product could be exploited in attacks aimed at industrial control systems (ICS). 

Researchers at cybersecurity firm Tenable discovered one critical and two high-severity vulnerabilities in ThinManager ThinServer, a thin client and RDP server management software offered by Rockwell. The flaws are tracked as CVE-2023-2914, CVE-2023-2915 and CVE-2023-2917.

The security holes have been described as improper input validation issues that can lead to integer overflow or path traversal. The flaws can be exploited by remote attackers — without prior authentication — by sending specially crafted synchronization protocol messages. 

Exploitation of the vulnerabilities can allow causing a denial-of-service (DoS) condition, deleting arbitrary files with system privileges, and uploading arbitrary files to any folder on the drive where ThinServer.exe is installed.

The vulnerabilities were reported to the vendor in May and Tenable released technical details on August 17, the same day Rockwell Automation informed customers about the availability of patches (advisory for registered users). Tenable has also developed proof-of-concept (PoC) exploits, but it has not made them public. 

Tenable told SecurityWeek that the only requirement for exploitation is access to the network hosting the vulnerable server. Exploitation directly from the internet is also possible if the server is connected and exposed to the web, but this goes against the vendor’s recommended best practices.

“Successful exploitation can allow complete attacker control of the ThinServer,” Tenable said. “The real world impact of this access depends on the environment, server configuration and the content types the server is configured on and intended to access.”

The company noted that the product is typically used for human-machine interfaces (HMIs) used to control and monitor industrial equipment. 

“An attacker would be able to give themself access to these HMIs. An attacker could also pivot from the server to attack other assets on the network,” Tenable said.

The US Cybersecurity and Infrastructure Security Agency (CISA) also published an advisory this week to inform organizations about these vulnerabilities. 

Rockwell Automation product vulnerabilities could be targeted by threat actors in their operations. It recently came to light that an unnamed APT has set its sights on two ControlLogix vulnerabilities that could be exploited to cause disruption or destruction in critical infrastructure organizations. 

Rockwell discovered what it described as a “new exploit capability”, but there had been no evidence of exploitation in the wild.