CVE-2026-2055 identifies a medium severity information disclosure vulnerability in the DHCP Client Information Handler component of D-Link DIR-605L and DIR-619L routers running firmware versions 2.06B01 and 2.13B01. The vulnerability allows remote attackers to manipulate an unspecified function within this component to disclose sensitive information from the device without requiring any authentication or user interaction. The attack vector is network-based, meaning an attacker can exploit the flaw remotely over the internet or local network. The disclosed information could include configuration details or network-related data that may facilitate further attacks such as targeted intrusions or reconnaissance. Notably, the affected devices are no longer supported by D-Link, and no patches or firmware updates have been released to remediate this issue. Public exploit code is available, increasing the likelihood of exploitation by malicious actors. The CVSS 4.0 vector indicates no privileges or user interaction are needed, and the vulnerability impacts confidentiality with limited scope. This vulnerability primarily affects legacy consumer-grade routers that may still be in use in home or small office environments, potentially exposing connected networks to information leakage risks.

For European organizations, the impact of CVE-2026-2055 centers on the potential exposure of sensitive network information through compromised D-Link DIR-605L and DIR-619L routers. This information disclosure can aid attackers in mapping internal network topologies, identifying connected devices, or harvesting configuration details that facilitate lateral movement or further exploitation. Although the vulnerability does not directly allow code execution or denial of service, the leaked information could be leveraged in multi-stage attacks, increasing overall risk. Small businesses and home offices using these legacy routers without vendor support are particularly vulnerable. The lack of patches means organizations cannot remediate the flaw through firmware updates, increasing reliance on network segmentation and device replacement. Additionally, the presence of public exploits raises the risk of opportunistic attacks targeting exposed routers, especially those accessible from the internet. This could lead to breaches of confidentiality and compromise of internal network security postures.

Given the absence of vendor patches for this vulnerability, European organizations should prioritize the following mitigations: 1) Conduct a thorough inventory to identify any D-Link DIR-605L or DIR-619L routers running the affected firmware versions within their networks. 2) Replace unsupported and vulnerable routers with currently supported models that receive security updates. 3) If immediate replacement is not feasible, isolate affected devices by placing them behind firewalls or network segmentation controls to restrict remote access, especially from untrusted external networks. 4) Disable remote management interfaces on these routers to minimize exposure. 5) Monitor network traffic for unusual DHCP-related activity or attempts to exploit the vulnerability. 6) Educate users and administrators about the risks of using unsupported network hardware and encourage timely hardware lifecycle management. 7) Implement network intrusion detection systems (NIDS) with signatures for known exploits targeting this vulnerability to detect potential attacks early.