CVE-2025-41732 is a stack-based buffer overflow vulnerability identified in WAGO Industrial-Managed-Switches, specifically due to unsafe usage of sscanf within the check_cookie() function. The vulnerability allows an unauthenticated remote attacker to send specially crafted input that overwrites fixed-size stack buffers, leading to memory corruption. This memory corruption can be exploited to execute arbitrary code on the device, resulting in full compromise. The vulnerability is critical with a CVSS 3.1 score of 9.8, reflecting its high impact on confidentiality, integrity, and availability, and the ease of exploitation without any authentication or user interaction. The flaw stems from improper input validation and unsafe parsing of cookie data, a common pitfall in embedded device software. The affected product, WAGO Industrial-Managed-Switches, is widely used in industrial control systems and manufacturing networks to manage and route network traffic. Compromise of these switches can allow attackers to intercept, manipulate, or disrupt industrial communications, potentially causing operational downtime or safety hazards. Although no public exploits or patches are currently available, the vulnerability's critical nature demands urgent attention from asset owners and security teams. The vulnerability was reserved in April 2025 and published in December 2025, indicating recent discovery and disclosure.

For European organizations, especially those in manufacturing, energy, transportation, and critical infrastructure sectors, this vulnerability poses a severe threat. WAGO switches are integral to industrial network management, and their compromise can lead to unauthorized access to sensitive operational data, disruption of industrial processes, and potential physical damage due to manipulation of control systems. The unauthenticated nature of the exploit means attackers can target these devices remotely without prior access, increasing the attack surface significantly. The full device compromise can facilitate lateral movement within industrial networks, enabling attackers to escalate privileges and access other critical systems. This could result in prolonged operational outages, financial losses, regulatory penalties, and damage to reputation. Given Europe's strong industrial base and reliance on automation, the impact could be widespread, affecting supply chains and critical services.

Organizations should immediately inventory and identify all WAGO Industrial-Managed-Switches within their networks. Until a vendor patch is released, network segmentation should be enforced to isolate these switches from untrusted networks and limit remote access. Deploy strict firewall rules to restrict management interface access to trusted IP addresses only. Implement network intrusion detection and prevention systems (IDS/IPS) with signatures or anomaly detection tuned for unusual traffic patterns targeting these devices. Monitor device logs and network traffic for signs of exploitation attempts, such as malformed packets or unexpected connections to the check_cookie() function endpoint. Engage with WAGO support channels to obtain any available vendor advisories or beta patches. Consider deploying virtual patching via network security appliances to block exploit attempts. Additionally, conduct regular security assessments and penetration tests focusing on industrial network components. Prepare incident response plans specific to industrial control system compromises to minimize downtime and impact.