CVE-2025-54401 identifies a stack-based buffer overflow vulnerability in the Planet WGR-500 router firmware version v1.3411b190912. The vulnerability resides in the formPingCmd functionality, which processes HTTP requests containing the 'submit-url' parameter. By sending a carefully crafted sequence of HTTP requests, an attacker can overflow a stack buffer, potentially overwriting return addresses or control data on the stack. This can lead to arbitrary code execution with the privileges of the affected process, which typically runs with elevated rights on the router. The vulnerability requires the attacker to have network access and low privileges (PR:L), but does not require user interaction (UI:N). The CVSS v3.1 score of 8.8 reflects the ease of exploitation (low attack complexity), the network attack vector, and the high impact on confidentiality, integrity, and availability. While no public exploits are currently known, the nature of stack-based buffer overflows makes this a critical concern, as successful exploitation could allow attackers to take full control of the device, intercept or manipulate network traffic, or disrupt network services. The lack of available patches at the time of publication increases the urgency for mitigation. The vulnerability is classified under CWE-121, a common and well-understood category of memory corruption bugs that have historically led to severe security breaches.

For European organizations, the impact of this vulnerability can be significant, especially for those relying on Planet WGR-500 routers in their network infrastructure. Successful exploitation could lead to unauthorized remote code execution, allowing attackers to gain control over the router. This compromises the confidentiality of network traffic passing through the device, potentially exposing sensitive data. Integrity can be undermined by attackers manipulating routing or firewall rules, enabling man-in-the-middle attacks or injecting malicious payloads. Availability is also at risk, as attackers could disrupt network connectivity by crashing or disabling the device. Critical sectors such as finance, healthcare, government, and telecommunications that depend on stable and secure network equipment may face operational disruptions, data breaches, or espionage. The vulnerability’s network-based attack vector means that attackers do not need physical access, increasing the threat surface. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the potential for rapid weaponization once details become widely known.

1. Immediate mitigation involves restricting network access to the management interface of the Planet WGR-500 routers, ideally limiting it to trusted internal networks or VPN connections. 2. Employ network segmentation to isolate vulnerable devices from critical infrastructure and sensitive data flows. 3. Monitor network traffic for unusual HTTP requests targeting the formPingCmd functionality or anomalous patterns indicative of exploitation attempts. 4. Deploy intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics capable of detecting buffer overflow attempts against this device. 5. Coordinate with the vendor to obtain and apply firmware updates or patches as soon as they become available. 6. If patches are delayed, consider temporary device replacement or disabling vulnerable services where feasible. 7. Conduct regular security audits and vulnerability assessments on network devices to identify and remediate similar issues proactively. 8. Educate network administrators about this vulnerability and ensure incident response plans include scenarios involving router compromise.