CVE-2025-53714 is a medium-severity vulnerability identified in the TP-Link TL-WR841N V11 router, specifically within the /userRpm/WzdWlanSiteSurveyRpm_AP.htm web interface file. The root cause is a lack of proper input parameter validation, which leads to a buffer overflow condition. This vulnerability falls under CWE-119, indicating improper restriction of operations within the bounds of a memory buffer. Exploiting this flaw allows an unauthenticated remote attacker to cause a denial-of-service (DoS) by crashing the web service of the device. The CVSS 4.0 score of 6.9 reflects a network attack vector with low attack complexity, no privileges or user interaction required, but with a high impact on availability. Notably, the vulnerability affects only devices that are no longer supported by TP-Link, meaning no official patches or updates are available. The absence of known exploits in the wild suggests it is not yet actively exploited, but the vulnerability remains a risk due to the widespread deployment of this router model in home and small office environments. The buffer overflow could be triggered by sending crafted HTTP requests to the vulnerable endpoint, causing the embedded web server to crash and disrupt network connectivity for users relying on this device.

For European organizations, the primary impact is availability disruption of network infrastructure relying on the TL-WR841N V11 router. This device is commonly used in small offices and residential settings, so organizations with remote or branch offices using this hardware could experience network outages, impacting business operations and communication. The denial-of-service could also be leveraged as part of a broader attack to cause operational disruption or as a stepping stone for further network reconnaissance. Given that the device is no longer supported, organizations cannot rely on vendor patches, increasing the risk of prolonged exposure. Additionally, the disruption of network services could affect compliance with EU regulations on service availability and incident response, especially for critical infrastructure or services. While confidentiality and integrity impacts are not indicated, the availability impact alone can have significant operational and reputational consequences.

Since the affected TP-Link TL-WR841N V11 devices are no longer supported and no patches are available, organizations should prioritize replacing these routers with currently supported models that receive security updates. As an immediate mitigation, network administrators should restrict access to the router's web management interface by limiting it to trusted internal networks and disabling remote management if enabled. Implementing network segmentation can reduce exposure by isolating vulnerable devices from critical systems. Monitoring network traffic for unusual HTTP requests targeting the /userRpm/WzdWlanSiteSurveyRpm_AP.htm endpoint can help detect exploitation attempts. Additionally, organizations should enforce strict firewall rules to block unsolicited inbound traffic to the router’s management ports. Regular inventory and asset management to identify and phase out unsupported devices is critical. For environments where replacement is not immediately feasible, deploying intrusion prevention systems (IPS) with custom signatures to detect and block exploit attempts may provide temporary protection.