CVE-2025-29743 is a medium severity vulnerability identified in the D-Link DIR-816 A2V1.1.0B05 router firmware. The vulnerability is a command injection flaw located in the /goform/delRouting endpoint. Command injection (CWE-77) occurs when untrusted input is improperly sanitized, allowing an attacker to execute arbitrary commands on the underlying operating system. In this case, the affected endpoint likely processes routing deletion requests without adequate input validation, enabling an attacker to inject malicious shell commands. The CVSS 3.1 base score of 6.5 reflects that the vulnerability can be exploited remotely over the network (AV:N) with low attack complexity (AC:L), requiring no privileges (PR:N) and no user interaction (UI:N). The impact is limited to partial confidentiality and integrity loss (C:L/I:L/A:N), meaning an attacker could potentially read or modify some data or configuration but not cause denial of service. No known exploits are currently reported in the wild, and no patches have been published yet. The vulnerability was reserved in March 2025 and publicly disclosed in April 2025. Given the nature of the device (a consumer or small office router), exploitation could allow an attacker to alter routing configurations, intercept or redirect network traffic, or gain further foothold within a network environment. However, the lack of authentication requirement and remote network vector increases the risk of exploitation, especially in environments where the device is exposed to untrusted networks or the internet directly.

For European organizations, this vulnerability poses a moderate risk primarily to small and medium enterprises (SMEs) and home office setups using the D-Link DIR-816 router. Successful exploitation could lead to unauthorized access to network routing configurations, enabling attackers to intercept sensitive communications, perform man-in-the-middle attacks, or pivot to internal systems. This could compromise confidentiality and integrity of data flows, potentially exposing corporate credentials, intellectual property, or personal data subject to GDPR regulations. While the vulnerability does not directly cause denial of service, the ability to manipulate routing could disrupt network operations or degrade performance. Organizations relying on these routers in critical infrastructure sectors or remote offices may face increased exposure, especially if devices are internet-facing or lack network segmentation. The absence of known exploits currently reduces immediate threat but does not eliminate risk, as public disclosure may prompt attackers to develop exploits. Additionally, the medium severity score suggests that while impactful, the vulnerability is not trivial to exploit at scale without some network access.

1. Immediate mitigation should include isolating affected D-Link DIR-816 routers from untrusted networks, especially the internet, by placing them behind firewalls or VPNs to restrict access to the /goform/delRouting endpoint. 2. Network administrators should monitor router logs and network traffic for unusual routing changes or suspicious command execution patterns. 3. Implement strict network segmentation to limit the impact of any compromised router, preventing lateral movement to critical systems. 4. Disable remote management interfaces on the router if not required, or restrict access to trusted IP addresses only. 5. Regularly audit and update router firmware; although no patch is currently available, vendors should be contacted for updates or workarounds. 6. Employ intrusion detection systems (IDS) with signatures targeting command injection attempts on router management endpoints. 7. Educate users and administrators about the risks of exposing router management interfaces and encourage best practices for device hardening. 8. Consider replacing vulnerable devices with models that have a stronger security posture if patching is not forthcoming.