Critical Vulns Discovered in Vendor Implementations of Key OT Protocol

Researchers from Claroty this week disclosed multiple critical vulnerabilities in vendor implementations of the Open Platform Communications (OPC) network protocol that is widely used in operational technology (OT) networks.

The flaws affect products from three vendors whose technologies are also being used as third-party components in multiple other white-label products running the OPC protocol. Claroty privately reported its vulnerability discoveries to the three vendors in 2020. The products have since been patched, prompting Claroty to publicly disclose the issue for the first time this week.

In a blog post, the vendor described the security issues as exposing organizations using the vulnerable products to distributed denial-of-service attacks, remote code execution, and leaks and theft of sensitive data.

"Many commercial [industrial control system] products use the OPC protocol for the secure exchange of information between devices across an operational technology network," says Uri Katz, protocol researcher at Claroty.

The protocol ensures interoperability between proprietary industrial control systems and is a critical piece of an OT network. Vulnerabilities in vendor implementations of the OPC protocol can have serious implications for the reliability and availability of devices, Katz says.

"OPC is a crucial part of many OT networks, and even creating denial-of-service conditions on OPC servers could critically impact OT processes," he adds. According to Katz, all of the vulnerabilities that Claroty discovered are trivial to exploit for attackers familiar with how the OPC protocol works.

Claroty, an OT security company, discovered the security bugs while conducting a broad vulnerability analysis of the OPC protocol in 2020. The company decided to investigate the protocol because of its wide use in industrial control system and OT environments. The analysis unearthed critical security issues in OPC implementations from three vendors: Softing Industrial Automation GmbH, Kepware PTC, and Matrikon Honeywell.

Claroty discovered two vulnerabilities in Softing's OPC library. One of them was a buffer-overflow issue (CVE-2020-14524) that, if exploited, could cause the server to crash. The other was a resource consumption bug (CVE-2020-14522) that gave attackers a way to trigger denial-of-service conditions against a server running the vulnerable protocol.

Calorty's analysis uncovered three security issues in Kepware products, ThingWorx Kepware Edge and KEPServerEX OPC Servers. Two of them were buffer overflow issues (CVE-2020-27265 and CVE-2020-27263), while the third was what is known as a use-after-free vulnerability (CVE-2020-27267). Two of the now-patched flaws allowed an unauthenticated attacker to run malicious code remotely on a vulnerable system.

Claroty found four critical vulnerabilities in the MatrikonOPC Tunneller by Matrikon Honeywell. The four flaws were a heap overflow remote code execution issue (CVE-2020-27297) that could allow for DDoS attacks; a heap out-of-bounds (OOB) memory issue (CVE-2020-27299) that could lead to information leaks, and two DDoS flaws (CVE-2020-27274 and CVE-2020-27295).

According to Katz, the OOB vulnerability is the most serious because it resides in functionality used by various products by multiple vendors. US-CERT and others have urged organizations running vulnerable products from each of the three vendors to upgrade to the latest versions of the software in each case to mitigate exposure to the newly disclosed threats.

Claroty's report comes amid suggestions of growing enterprise interest in OT security, an area that has been somewhat overlooked because of misconceived perceptions about the environment being air-gapped — and therefore immune to attacks. According to a new report by Research and Markets, the global OT security market will grow to $18.3 billion over the next two years as organizations rush to address gaps in their OT environments.