CVE-2022-44363 is a critical buffer overflow vulnerability identified in the Tenda i21 router firmware version V1.0.0.14(4656). The vulnerability occurs via the /goform/setSnmpInfo endpoint, which is likely part of the router's web management interface used to configure SNMP (Simple Network Management Protocol) settings. A buffer overflow (CWE-787) happens when more data is written to a buffer than it can hold, potentially allowing an attacker to overwrite adjacent memory. This can lead to arbitrary code execution, denial of service, or system compromise. The vulnerability is remotely exploitable over the network (Attack Vector: Network) without requiring any authentication or user interaction, making it highly accessible to attackers. The CVSS v3.1 base score is 9.8, indicating critical severity, with high impact on confidentiality, integrity, and availability. The vulnerability allows an unauthenticated attacker to send crafted requests to the vulnerable endpoint, triggering the overflow and potentially gaining full control over the device. No patches or vendor advisories are currently linked, and no known exploits in the wild have been reported yet. Given the nature of the device—a consumer or small office router—successful exploitation could enable attackers to intercept or manipulate network traffic, pivot into internal networks, or disrupt connectivity.

For European organizations, especially small and medium enterprises (SMEs) and home office users relying on Tenda i21 routers, this vulnerability poses a significant risk. Exploitation could lead to full compromise of the router, allowing attackers to intercept sensitive communications, inject malicious traffic, or establish persistent footholds within corporate or home networks. This threatens confidentiality by exposing internal data, integrity by enabling traffic manipulation, and availability by causing device crashes or network outages. Critical infrastructure or organizations with remote workers using vulnerable devices may face increased risk of lateral movement by attackers. The lack of authentication and user interaction requirements means attacks can be automated and launched at scale, increasing the threat surface. Additionally, compromised routers could be recruited into botnets, amplifying broader cyber threats. The absence of patches increases the urgency for mitigation. Overall, the vulnerability undermines network security and trust in perimeter devices, which are foundational to organizational cybersecurity postures in Europe.

1. Immediate mitigation should include isolating vulnerable Tenda i21 routers from critical network segments and restricting remote management access, especially from untrusted networks. 2. Disable SNMP or the /goform/setSnmpInfo functionality if possible, or restrict access to trusted IP addresses only. 3. Monitor network traffic for unusual requests targeting the /goform/setSnmpInfo endpoint or signs of exploitation attempts. 4. Implement network-level protections such as firewall rules to block unsolicited inbound traffic to router management interfaces. 5. Encourage users and administrators to replace vulnerable devices with updated or alternative hardware if no firmware updates are available. 6. Regularly check Tenda’s official channels for firmware updates or security advisories addressing this vulnerability. 7. Employ intrusion detection/prevention systems (IDS/IPS) with signatures tuned to detect buffer overflow attempts against this endpoint. 8. Conduct internal audits to identify all Tenda i21 devices in use and document their firmware versions and network exposure. These steps go beyond generic advice by focusing on specific endpoint isolation, access control, and monitoring tailored to the vulnerability’s characteristics.