OPC UA Pwn2Own 2023 Resource Exhaustion Exploit
Prosys OPC UA Simulation Server and Prosys OPC UA Browser were selected as targets at the Pwn2Own Miami 2023 ICS/SCADA-themed contest that was hosted by Zero Day Initiative (ZDI) on February 14-16, 2023. Security research teams were invited to compete for prizes for finding security exploits in various industrial control system (ICS) products, namely in the categories for OPC Unified Architecture (OPC UA) Servers, OPC UA Clients, Data Gateways, and Edge systems.
Several exploits were found from the products during the three days (see results for Day 1, Day 2 and Day 3). Prosys OPC UA Browser did not get any attacks, but Prosys OPC UA Simulation Server was successfully exploited during Day 3 when
“Claroty [Research, Team82 – Vera Mens, Noam Moshe, Uri Katz, Sharon Brizinov] used a resource exhaustion in their DoS attack against the Prosys OPC UA Simulation Server.”.
ZDI and Claroty Research disclosed the exploit’s details to us so we could fix the issue. It turned out that there were a couple of vulnerabilities in the Prosys OPC UA SDK for Java that that enabled the team to execute the attack in 5 minutes. The fix to the SDK and our other products is now available. We recommend that all our customers update their products accordingly as soon as possible and release updated versions of their products to secure the industry from this exploit in future.
We have evaluated the exploit with CVSS Base Score 7.5 and Vector String (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
The exploit enables an unauthorized attacker to block OPC UA server applications so that they can no longer serve client applications.
The vulnerability has been given an identifier ZDI-CAN-20503.
Affected Prosys OPC products
Affected Prosys OPC UA Products
- Prosys OPC UA SDK for Java 4.10.2 and earlier (and all server products built with it)
- Prosys OPC UA Simulation Server 5.4.2 and earlier
- Prosys OPC UA Modbus Server 1.4.20 and earlier
- Prosys OPC UA Historian 1.2.0 and earlier
The issue has been fixed in Prosys OPC UA SDK for Java 4.10.4 and the following applications Simulation Server 5.4.4, Modbus Server 1.4.22 and Historian 1.2.2, and we encourage everyone to update to these versions.
More Security Information
You will find the currently announced security issues in Prosys OPC products from the blog under the #Security tag.
You might also like to read about the OPC UA Security Process of the OPC Foundation.