CVE-2022-46350 is a medium-severity vulnerability affecting Siemens SCALANCE X204RNA devices, specifically the HSR and PRP variants, including their EEC models. All versions prior to V3.2.7 are impacted. The vulnerability is classified as CWE-80, which involves improper neutralization of script-related HTML tags, leading to a basic Cross-Site Scripting (XSS) flaw in the integrated web server of these devices. This XSS vulnerability allows an attacker to craft malicious links that, when accessed by an unsuspecting user (such as an administrator or operator managing the device via its web interface), can execute arbitrary scripts in the context of the victim’s browser session. The CVSS v3.1 base score is 6.1, reflecting a medium severity level, with the vector indicating network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), user interaction required (UI:R), scope changed (S:C), and impacts on confidentiality and integrity (C:L/I:L) but no impact on availability (A:N). The vulnerability does not require authentication, but does require the user to interact with a malicious link, which could be delivered via phishing or other social engineering techniques. Exploitation could allow an attacker to perform actions on behalf of the user, potentially altering device configurations or stealing sensitive information accessible through the web interface. No known exploits in the wild have been reported to date, and Siemens has not provided explicit patch links in the provided data, though version 3.2.7 or later presumably addresses the issue. The affected devices are industrial networking components used in high-availability and redundancy protocols (HSR and PRP), commonly deployed in critical infrastructure and industrial automation environments. The vulnerability’s scope change indicates that successful exploitation could affect resources beyond the initially vulnerable component, potentially impacting the broader network environment managed by these devices.

For European organizations, particularly those in industrial sectors such as manufacturing, energy, transportation, and utilities, this vulnerability poses a risk to operational technology (OT) networks. SCALANCE X204RNA devices are often integral to ensuring network redundancy and reliability in critical systems. An attacker exploiting this XSS flaw could hijack administrative sessions, leading to unauthorized configuration changes, leakage of sensitive network information, or pivoting to other network segments. This could degrade network integrity and confidentiality, potentially causing operational disruptions or enabling further attacks. Given the role of these devices in high-availability networks, any compromise could have cascading effects on industrial processes and safety systems. Although availability impact is rated none in CVSS, indirect effects from misconfiguration or further exploitation could affect system uptime. The requirement for user interaction limits mass exploitation but targeted spear-phishing campaigns against network administrators or engineers could be effective. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as these devices are deployed in critical infrastructure sectors that are frequent targets of cyber espionage and sabotage in Europe.

1. Immediate upgrade of all affected SCALANCE X204RNA devices to firmware version 3.2.7 or later, as this version addresses the vulnerability. 2. Restrict access to the device web interfaces to trusted networks and users only, ideally isolating management interfaces from general enterprise networks and the internet. 3. Implement strong network segmentation and firewall rules to limit exposure of these devices. 4. Educate and train network administrators and operators on phishing and social engineering risks to reduce the chance of user interaction with malicious links. 5. Employ web browser security controls such as Content Security Policy (CSP) and script-blocking extensions where feasible to mitigate XSS impact. 6. Monitor network and device logs for unusual access patterns or configuration changes that could indicate exploitation attempts. 7. Use multi-factor authentication (MFA) for accessing management interfaces if supported, to reduce the risk of session hijacking. 8. Regularly audit device firmware versions and configurations to ensure compliance with security policies. 9. Coordinate with Siemens support channels for any additional patches or mitigations and subscribe to their security advisories for timely updates.