CVE-2025-8175 is a high-severity vulnerability affecting the D-Link DI-8400 router running firmware version 16.07.26A1. The flaw exists in the jhttpd component, specifically within the usb_paswd.asp file, where improper handling of the 'share_enable' argument leads to a NULL pointer dereference. This vulnerability can be triggered remotely without authentication or user interaction, making it accessible to attackers over the network. The NULL pointer dereference typically results in a denial-of-service (DoS) condition by crashing the affected service or device, potentially disrupting network connectivity for users relying on the router. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L), no user interaction (UI:N), and high impact on availability (VA:H), with no impact on confidentiality or integrity. Although no known exploits are currently observed in the wild, public disclosure of the exploit code increases the risk of exploitation. The vulnerability's root cause is the failure to properly validate or handle the 'share_enable' parameter, which when manipulated, causes the software to dereference a null pointer, leading to a crash of the jhttpd service or the entire device. This can cause network outages and service interruptions for organizations using the affected hardware. Given the critical role of routers in network infrastructure, exploitation could disrupt business operations and degrade network reliability.

For European organizations, the impact of this vulnerability can be significant, especially for those relying on the D-Link DI-8400 router in their network infrastructure. A successful attack could cause denial-of-service conditions, interrupting internet connectivity and internal network communications. This disruption can affect business continuity, remote work capabilities, and access to cloud services. Critical sectors such as finance, healthcare, and government agencies could face operational downtime, leading to financial losses and reputational damage. Additionally, the lack of confidentiality or integrity impact means data theft or manipulation is unlikely, but availability loss alone can have severe consequences. Organizations with limited IT resources or those slow to apply patches may be particularly vulnerable. The public availability of exploit code increases the risk of opportunistic attacks, including from cybercriminals targeting less protected networks. Furthermore, the vulnerability could be leveraged as part of a larger attack chain, for example, to create network outages during ransomware attacks or other cyber incidents.

1. Immediate mitigation should include identifying all D-Link DI-8400 devices running firmware version 16.07.26A1 within the network. 2. Since no official patch links are currently available, organizations should contact D-Link support for firmware updates or advisories addressing this vulnerability. 3. As a temporary workaround, restrict remote access to the router's management interface by implementing network segmentation and firewall rules that limit access to trusted IP addresses only. 4. Monitor network traffic for unusual requests targeting the usb_paswd.asp endpoint or suspicious manipulation of the 'share_enable' parameter. 5. Implement intrusion detection/prevention systems (IDS/IPS) with signatures to detect attempts to exploit this vulnerability once available. 6. Plan for rapid deployment of firmware updates once released by the vendor. 7. Maintain regular backups of router configurations to enable quick recovery in case of device crashes. 8. Educate network administrators about this vulnerability and ensure they follow best practices for secure router management, including disabling unnecessary services and changing default credentials. 9. Consider replacing affected devices with newer, supported hardware if patches are delayed or unavailable.