CVE-2025-71057 is a security vulnerability identified in the D-Link Wireless N 300 ADSL2+ Modem Router DSL-124 ME_1.00 firmware version 1.00. The flaw arises from improper session management that fails to adequately verify the legitimacy of session tokens against the IP address of the authenticated user. Specifically, the router's session handling mechanism allows an attacker to spoof the IP address of a legitimate authenticated user and thereby hijack the session. This means that an attacker can gain unauthorized access to the router's management interface or network resources by masquerading as a trusted user without needing valid credentials or user interaction. The vulnerability does not currently have a CVSS score and no public exploits have been reported, but the technical details indicate a critical weakness in session validation logic. The lack of patch links suggests that a fix may not yet be available, emphasizing the need for immediate attention by affected users. This vulnerability could be exploited remotely if the router's management interface is exposed or through local network access, increasing the attack surface. The issue compromises confidentiality and integrity by allowing attackers to intercept or manipulate network traffic and device settings. Given the widespread use of D-Link routers in residential and small business environments, the vulnerability could have broad implications if exploited.

The potential impact of CVE-2025-71057 is significant for organizations and individuals using the affected D-Link router model. Successful exploitation allows attackers to hijack authenticated sessions, granting unauthorized access to the router's administrative interface and potentially the internal network. This can lead to interception of sensitive data, unauthorized configuration changes, insertion of malicious firmware or DNS settings, and further lateral movement within the network. For small businesses and home users, this could result in data breaches, loss of privacy, and network downtime. Enterprises relying on these devices for remote or branch connectivity may face operational disruptions and increased risk of compromise. The vulnerability's exploitation does not require user interaction or authentication, making it easier for attackers to execute automated attacks. Although no known exploits are currently in the wild, the vulnerability's nature and the device's market penetration suggest a high risk if weaponized. The absence of a patch increases exposure time, elevating the threat level until mitigations are applied.

To mitigate CVE-2025-71057, affected users should first verify if a firmware update addressing the vulnerability has been released by D-Link and apply it immediately. In the absence of an official patch, users should restrict access to the router's management interface by disabling remote administration and limiting local network access to trusted devices only. Implement network segmentation to isolate the router management interface from general user traffic. Employ strong network security controls such as MAC address filtering and IP source verification where possible. Monitor network traffic for signs of IP spoofing or unusual session activity. Change default credentials and use strong, unique passwords to reduce the risk of unauthorized access. Additionally, consider deploying network intrusion detection systems (NIDS) capable of detecting session hijacking attempts. Organizations should maintain an inventory of affected devices and plan for replacement or upgrade if patches are unavailable or delayed. Regularly review router logs for suspicious activity and educate users about the risks of unsecured network devices.