CVE-2025-7910 is a critical security vulnerability identified in the D-Link DIR-513 router, specifically version 1.10. The flaw exists in the Boa Webserver component, which is embedded in the device's firmware to handle HTTP requests. The vulnerability arises from improper handling of the 'curTime' argument in the /goform/formSetWanNonLogin endpoint, where the use of the unsafe sprintf function leads to a stack-based buffer overflow. This type of overflow occurs when data exceeding the allocated buffer size is written to the stack, potentially overwriting adjacent memory, including control flow data such as return addresses. Because the vulnerability is remotely exploitable without authentication or user interaction, an attacker can send specially crafted HTTP requests to the affected endpoint to trigger the overflow. Successful exploitation could allow an attacker to execute arbitrary code with elevated privileges on the router, leading to full device compromise. This could enable attackers to manipulate network traffic, intercept sensitive data, or use the device as a foothold for further attacks within the network. Although the vulnerability has been publicly disclosed and proof-of-concept exploits may exist, there are no confirmed reports of active exploitation in the wild. Importantly, the affected product is no longer supported by D-Link, meaning no official patches or firmware updates are available to remediate the issue. This significantly increases the risk for users who continue to operate these devices in production environments.

For European organizations, the impact of CVE-2025-7910 can be substantial, especially for small and medium enterprises or residential users relying on the D-Link DIR-513 router for internet connectivity. Compromise of these routers can lead to unauthorized access to internal networks, interception of confidential communications, and potential lateral movement to other critical systems. Given the router’s role as a network gateway, attackers could manipulate DNS settings, redirect traffic to malicious sites, or deploy man-in-the-middle attacks. The lack of vendor support and patches means organizations cannot rely on firmware updates to mitigate the risk, increasing exposure. Additionally, the high CVSS score (8.7) reflects the ease of remote exploitation and the severe consequences on confidentiality, integrity, and availability. European organizations in sectors with stringent data protection requirements, such as finance, healthcare, and government, may face regulatory and reputational damage if compromised. Furthermore, the vulnerability could be leveraged by cybercriminals or state-sponsored actors targeting European infrastructure, especially where legacy or unsupported network equipment is still in use.

Given the absence of official patches, European organizations should prioritize immediate mitigation steps beyond generic advice. First, identify and inventory all D-Link DIR-513 devices running firmware version 1.10 within the network. Where possible, replace these devices with supported, updated hardware that receives regular security patches. If replacement is not immediately feasible, isolate the affected routers by placing them behind additional firewalls or network segmentation to restrict inbound access to the vulnerable webserver interface. Disable remote management features and restrict access to the router’s web interface to trusted internal IP addresses only. Employ network intrusion detection systems (NIDS) to monitor for suspicious HTTP requests targeting /goform/formSetWanNonLogin or anomalous traffic patterns indicative of exploitation attempts. Additionally, implement strict egress filtering to prevent compromised devices from communicating with external command and control servers. Regularly review router logs for signs of exploitation attempts. Finally, educate network administrators and users about the risks of using unsupported network equipment and the importance of timely hardware upgrades.