CVE-2025-48020 is a vulnerability identified in the Vnet/IP Interface Package developed by Yokogawa Electric Corporation, specifically affecting versions R1.07.00 and earlier used in CENTUM VP R6 (VP6C3300) and R7 (VP7C3300) systems. The vulnerability is classified as CWE-617, a reachable assertion, which means that under certain conditions, the software encounters an assertion failure triggered by malicious input. In this case, if the affected Vnet/IP software stack receives specially crafted network packets, it can cause the process to terminate abruptly, resulting in a denial-of-service (DoS) condition. The CVSS 4.0 vector indicates the attack requires adjacent network access (AV:A), has high attack complexity (AC:H), no privileges or user interaction are needed (PR:N, UI:N), and the impact is high on availability (VA:H) but none on confidentiality or integrity. The vulnerability affects critical industrial control systems (ICS) that rely on Yokogawa’s Vnet/IP for communication within the CENTUM VP distributed control system (DCS) environment. Since no patches or known exploits are currently available, the threat primarily lies in potential disruption of industrial processes through network-based attacks. The assertion failure could cause system instability or downtime, impacting operational continuity in industrial environments.

The primary impact of CVE-2025-48020 is denial of service due to process termination of the Vnet/IP software stack, which can disrupt industrial control system operations. This can lead to temporary loss of monitoring and control capabilities in critical infrastructure such as manufacturing plants, power generation, water treatment, and other industrial environments using Yokogawa’s CENTUM VP systems. The disruption could cause operational delays, safety risks, and financial losses. Since the vulnerability requires adjacent network access and high attack complexity, exploitation is less trivial but remains a concern in environments where attackers can gain network proximity, such as through compromised internal networks or insider threats. The lack of confidentiality or integrity impact reduces the risk of data theft or manipulation, but availability impact on critical ICS components can have severe consequences. Organizations with large-scale industrial automation deployments are particularly vulnerable to operational disruptions and potential cascading effects in supply chains or critical services.

To mitigate CVE-2025-48020, organizations should implement strict network segmentation to isolate Vnet/IP-enabled devices and limit access to trusted network segments only. Employing robust network monitoring and anomaly detection can help identify suspicious crafted packets targeting the Vnet/IP stack. Since no patches are currently available, applying virtual patching via intrusion prevention systems (IPS) with custom signatures to detect and block malformed packets is advisable. Regularly auditing and restricting access to the adjacent network where the Vnet/IP devices reside will reduce exposure. Additionally, organizations should prepare incident response plans for potential DoS events affecting industrial control systems and coordinate with Yokogawa for timely updates or patches. Testing and validation of network controls in industrial environments are critical to ensure operational continuity while mitigating this vulnerability.