CVE-2025-45489 is a command injection vulnerability identified in the Linksys E5600 router firmware version 1.1.0.26. The flaw exists in the runtime.ddnsStatus DynDNS function, specifically via the hostname parameter. Command injection vulnerabilities occur when untrusted input is passed to a system shell or command interpreter without proper sanitization, allowing an attacker to execute arbitrary commands on the affected device. In this case, the hostname parameter used by the DynDNS function does not properly validate or sanitize input, enabling an attacker to inject malicious commands. The vulnerability is remotely exploitable over the network without requiring authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The CVSS v3.1 base score is 6.5, categorizing it as a medium severity issue. The impact primarily affects confidentiality and integrity, as the attacker could execute commands to manipulate device configuration or intercept network traffic, but it does not directly impact availability. No known exploits are currently reported in the wild, and no patches or vendor advisories have been published yet. The vulnerability is associated with CWE-77 (Improper Neutralization of Special Elements used in a Command ('Command Injection')). Given the nature of the device—a consumer-grade router—successful exploitation could allow attackers to gain control over network traffic routing, perform man-in-the-middle attacks, or pivot into internal networks, posing significant risks to network security and privacy.

For European organizations, the exploitation of this vulnerability in Linksys E5600 routers could lead to unauthorized command execution on network gateway devices. This could compromise the confidentiality of sensitive communications, allow attackers to alter network configurations, or enable persistent access to internal networks. Organizations relying on these routers for home offices, small branch offices, or remote workers may face increased risk of data interception or lateral movement by attackers. The lack of authentication requirement lowers the barrier for exploitation, increasing the threat level. While the vulnerability does not directly affect availability, the potential for data leakage and integrity compromise could disrupt business operations and erode trust. Additionally, regulatory compliance frameworks such as GDPR impose strict requirements on data protection; a breach resulting from this vulnerability could lead to legal and financial penalties for European entities.

To mitigate this vulnerability, European organizations should first identify any deployment of Linksys E5600 routers running firmware version 1.1.0.26. Until an official patch is released, organizations should consider the following specific measures: 1) Disable the DynDNS feature if it is not essential to reduce the attack surface. 2) Restrict network access to the router's management interfaces by implementing firewall rules that limit access to trusted IP addresses only. 3) Monitor network traffic for unusual DNS or command execution patterns that could indicate exploitation attempts. 4) Employ network segmentation to isolate vulnerable devices from critical systems and sensitive data. 5) Regularly check for firmware updates from Linksys and apply patches promptly once available. 6) Educate users about the risks of using default or outdated router firmware and encourage timely updates. 7) Consider replacing affected devices with models that have received security updates if patching is delayed.