CVE-2025-26389 is a critical security vulnerability identified in Siemens OZW672 and OZW772 devices running versions prior to 8.0. The vulnerability arises from improper neutralization of special elements in the input parameters of the `exportDiagramPage` endpoint of the device's web service. Specifically, the input parameters are not properly sanitized, allowing an unauthenticated remote attacker to perform OS command injection. This means that an attacker can craft malicious input to execute arbitrary operating system commands on the affected device with root-level privileges. Given the root access level, the attacker can fully compromise the device, potentially leading to complete control over the system, data exfiltration, disruption of services, or using the device as a pivot point for further network attacks. The vulnerability has a CVSS 3.1 base score of 10.0, indicating it is critical, with attack vector network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and scope changed (S:C). The impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). No patches are currently linked, and there are no known exploits in the wild as of the publication date. The vulnerability is categorized under CWE-78 (Improper Neutralization of Special Elements used in an OS Command Injection). This type of vulnerability is particularly dangerous in industrial control systems or networked devices like Siemens OZW series, which are often used in critical infrastructure environments. The ability to execute arbitrary commands remotely without authentication makes this a severe threat that requires immediate attention from affected organizations.

For European organizations, especially those operating critical infrastructure, manufacturing, or industrial automation systems using Siemens OZW672 or OZW772 devices, this vulnerability poses a significant risk. Exploitation could lead to unauthorized control over essential operational technology (OT) devices, causing operational disruptions, safety hazards, and potential physical damage. Confidentiality breaches could expose sensitive operational data or intellectual property. Integrity compromises could allow attackers to manipulate device behavior, leading to incorrect system outputs or unsafe conditions. Availability impacts could result in denial of service or system outages, affecting production lines or infrastructure services. Given the root-level access achievable, attackers could also establish persistent footholds within networks, facilitating further lateral movement or espionage. The lack of authentication and user interaction requirements increases the likelihood of exploitation, especially if devices are exposed to untrusted networks or insufficiently segmented environments. The critical severity underscores the urgency for European organizations to assess their exposure and implement mitigations promptly to avoid operational and reputational damage.

1. Immediate network segmentation: Isolate Siemens OZW672 and OZW772 devices from general IT networks and restrict access to trusted management networks only. 2. Implement strict firewall rules to block external access to the `exportDiagramPage` endpoint and other web services on these devices, allowing only authorized IP addresses. 3. Monitor network traffic for unusual requests targeting the vulnerable endpoint, employing intrusion detection/prevention systems (IDS/IPS) with custom signatures for command injection patterns. 4. Disable or restrict the use of the vulnerable web service endpoint if possible until a vendor patch is available. 5. Apply vendor-provided patches or firmware updates as soon as they are released; maintain close communication with Siemens for updates. 6. Conduct regular vulnerability scans and penetration tests focusing on OT devices to detect similar injection flaws. 7. Employ application-layer gateways or web application firewalls (WAF) capable of sanitizing or blocking malicious input to the device’s web services. 8. Enforce strict access controls and authentication mechanisms on management interfaces to reduce exposure. 9. Maintain comprehensive asset inventories to identify all affected devices and prioritize remediation efforts. 10. Train OT and security personnel on recognizing and responding to exploitation attempts targeting industrial devices.