CVE-2025-53711 is a classic buffer overflow vulnerability (CWE-120) found in TP-Link Systems INC. routers TL-WR841N v11, TL-WR842ND v2, and TL-WR494N v3. The vulnerability resides in the /userRpm/WlanNetworkRpm.htm web interface file, where input parameters are not properly validated before being copied into a buffer. This lack of bounds checking allows an attacker to overflow the buffer, causing the web service to crash and resulting in a denial-of-service (DoS) condition. The attack can be launched remotely over the network, but requires high privileges (authentication) to access the vulnerable interface, limiting the attack surface. The affected products are no longer supported by TP-Link, and no patches or updates have been released to address this issue. The CVSS 4.0 base score is 6.9, reflecting network attack vector, low attack complexity, no user interaction, but requiring privileges and causing high impact on availability. No known exploits have been reported in the wild. The vulnerability is tied to classic buffer overflow issues (CWE-120 and CWE-119), which historically have been exploited for code execution, but in this case, the impact is limited to DoS due to the nature of the overflow and access restrictions.

The primary impact of CVE-2025-53711 is denial-of-service, where the router's web management service crashes, potentially disrupting network management and connectivity. For organizations relying on these TP-Link models, this can lead to temporary loss of administrative access to the device, complicating network operations and incident response. While the vulnerability does not directly allow remote code execution or data compromise, the DoS condition can be leveraged in targeted attacks to degrade network availability. Since these devices are often deployed in small office/home office (SOHO) environments, the impact is more pronounced for smaller organizations or home users without redundant network infrastructure. The lack of vendor support and patches increases risk, as no official remediation is available. Attackers with valid credentials could exploit this vulnerability remotely, making insider threats or compromised credentials a significant risk factor. Overall, the threat could disrupt network stability and availability, affecting business continuity and user productivity.

Given the absence of official patches due to end-of-life status of the affected devices, mitigation should focus on compensating controls. First, organizations should prioritize replacing these legacy TP-Link routers with supported models that receive security updates. If immediate replacement is not feasible, restrict access to the router's management interface by implementing network segmentation and firewall rules to limit access only to trusted administrators. Enforce strong authentication mechanisms and monitor for unusual login attempts to reduce the risk of credential compromise. Disable remote management features if not required to minimize exposure. Regularly back up router configurations to enable rapid recovery in case of service disruption. Network administrators should also monitor router logs and network traffic for signs of exploitation attempts targeting the vulnerable endpoint. Finally, educating users about the risks of using unsupported hardware can help drive timely upgrades and reduce exposure.