CVE-2025-71057 is a vulnerability identified in the D-Link Wireless N 300 ADSL2+ Modem Router DSL-124 ME_1.00 firmware version ME_1.00. The root cause is improper session management, specifically allowing attackers to hijack active sessions by spoofing the IP address of an authenticated user. This vulnerability relates to CWE-384 (Session Fixation), CWE-287 (Improper Authentication), and CWE-345 (Insufficient Verification of Data Authenticity), indicating that the router fails to properly verify session tokens or authenticate session requests robustly. The attack vector is network-based (AV:N), requiring no privileges (PR:N) or user interaction (UI:N), making it relatively easy to exploit remotely. The impact on confidentiality is low, but the integrity impact is high, as attackers can perform unauthorized actions within the router’s management interface or network. Availability is not affected. The CVSS v3.1 base score is 8.2, reflecting the high risk posed by this vulnerability. No patches or fixes have been published yet, and no known exploits have been observed in the wild. The vulnerability was reserved in January 2026 and published in February 2026, indicating recent discovery. The affected device is commonly used in home and small office environments, which may be part of larger organizational networks, increasing the risk of lateral movement or network compromise if exploited.

The primary impact of CVE-2025-71057 is unauthorized access and control over the affected router’s management interface through session hijacking. Attackers can impersonate authenticated users by spoofing their IP addresses, potentially changing router configurations, intercepting or redirecting network traffic, or disabling security features. This compromises the integrity of network operations and can facilitate further attacks such as man-in-the-middle, data interception, or network disruption. Organizations relying on these routers for internet connectivity or internal network segmentation may face increased risk of network compromise. The vulnerability’s ease of exploitation and lack of required authentication make it particularly dangerous in environments where these devices are exposed to untrusted networks. The absence of patches exacerbates the threat, leaving devices vulnerable until mitigations or firmware updates are deployed. This could impact confidentiality indirectly if attackers gain access to sensitive network traffic or credentials through compromised routers.

1. Network Segmentation: Isolate affected routers from untrusted networks and restrict management interface access to trusted IP addresses or VLANs. 2. Access Controls: Implement strict firewall rules to limit remote access to the router’s management interface, ideally allowing only local or VPN-based connections. 3. Monitoring and Logging: Enable detailed logging on routers and network devices to detect unusual session activity or IP spoofing attempts. 4. Firmware Updates: Regularly check for official firmware updates from D-Link and apply patches immediately once available. 5. Replace Vulnerable Devices: For critical environments, consider replacing affected routers with models that have no known session management vulnerabilities. 6. Use Strong Authentication: Where possible, enable multi-factor authentication or stronger authentication mechanisms on router management interfaces. 7. Network Intrusion Detection: Deploy IDS/IPS solutions capable of detecting IP spoofing and session hijacking attempts. 8. Educate Network Administrators: Train staff to recognize signs of session hijacking and enforce best practices for router configuration and management.