CVE-2025-7762 is a critical stack-based buffer overflow vulnerability identified in the D-Link DI-8100 router, specifically affecting firmware version 16.07.26A1. The vulnerability resides in the HTTP Request Handler component, particularly in the processing of the /menu_nat_more.asp file. An attacker can remotely exploit this flaw by sending specially crafted HTTP requests to the affected endpoint, causing a stack-based buffer overflow. This overflow can lead to arbitrary code execution, potentially allowing an attacker to take full control of the device without requiring user interaction or prior authentication. The vulnerability has a CVSS 4.0 base score of 8.7, indicating high severity, with attack vector being network-based (remote), low attack complexity, no privileges required, and no user interaction needed. The impact metrics indicate high confidentiality, integrity, and availability impacts, meaning an attacker could exfiltrate sensitive data, modify device configurations, or disrupt network services. Although no public exploits are currently known to be in the wild, the vulnerability details have been disclosed publicly, increasing the risk of exploitation by threat actors. The lack of available patches at this time further exacerbates the risk. Given the critical nature of this flaw and the widespread use of D-Link DI-8100 routers in various enterprise and ISP environments, this vulnerability poses a significant threat to network security.

For European organizations, the exploitation of CVE-2025-7762 could have severe consequences. Many enterprises and ISPs in Europe deploy D-Link DI-8100 routers for network routing and NAT services. Successful exploitation could allow attackers to gain unauthorized access to internal networks, intercept or manipulate sensitive communications, and disrupt critical network infrastructure. This could lead to data breaches involving personal data protected under GDPR, resulting in regulatory fines and reputational damage. Additionally, compromised routers could be used as pivot points for lateral movement within corporate networks or as part of botnets for broader attacks. The high availability impact means that network outages or degraded service quality could affect business continuity. Given the remote exploitability and no requirement for authentication, attackers could target vulnerable devices en masse, increasing the risk for organizations with limited network segmentation or outdated device inventories.

European organizations should immediately identify any D-Link DI-8100 devices running firmware version 16.07.26A1 within their networks. Since no official patches are currently available, organizations should implement compensating controls such as: 1) Restricting access to the management interfaces of affected devices by limiting inbound HTTP traffic to trusted IP addresses or internal networks only. 2) Deploying network-based intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection rules to identify and block exploit attempts targeting /menu_nat_more.asp or suspicious HTTP requests. 3) Isolating vulnerable devices on segmented network zones with strict firewall rules to minimize potential lateral movement. 4) Monitoring device logs and network traffic for unusual activity indicative of exploitation attempts. 5) Planning for prompt firmware updates once vendor patches are released and testing them in controlled environments before deployment. 6) Considering device replacement if patching is delayed or unsupported, especially for critical infrastructure. 7) Educating IT staff about the vulnerability and ensuring incident response plans include steps for this specific threat.