Vulnerability · Published May 7, 2024 · Assigned by zdi

CVE-2023-27321OPC Foundation UA .NET Standard ConditionRefresh Resource Exhaustion Denial-of-Service Vulnerability

High 7.5

In plain English

A high-severity uncontrolled resource consumption in UA .NET Standard from OPC Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.0% (higher than 64% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.0)7.5High

Exploit odds (30 days)1.0%top 35.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

OPC Foundation UA .NET Standard ConditionRefresh Resource Exhaustion Denial-of-Service Vulnerability. This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of OPC Foundation UA .NET Standard. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of OPC UA ConditionRefresh requests. By sending a large number of requests, an attacker can consume all available resources on the server. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-20505.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
NuGet	opcfoundation.netstandard.opc.ua.server	1.4.371.86	GHSA-vpf7-r2fv-75m9

Affected products (as reported)

Vendor	Product	Versions
OPC Foundation	UA .NET Standard	1.4.371.60

Weakness: CWE-400 · Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

ZDI-23-548 x_research-advisory
vendor-provided URL vendor-advisory