CVE-2022-40100 is a critical command injection vulnerability identified in the Tenda i9 router firmware version 1.0.0.8(3828). The vulnerability resides in the FormexeCommand function, which improperly handles user input, allowing an attacker to inject and execute arbitrary commands on the device. This type of vulnerability is classified under CWE-77 (Improper Neutralization of Special Elements used in a Command ('Command Injection')). The CVSS v3.1 base score of 9.8 reflects the high severity, indicating that the vulnerability can be exploited remotely over the network (AV:N), requires no privileges (PR:N), and no user interaction (UI:N). Successful exploitation can lead to full compromise of the device, impacting confidentiality, integrity, and availability. Attackers could leverage this flaw to execute malicious commands, potentially gaining control over the router, intercepting or manipulating network traffic, deploying malware, or pivoting to other devices within the network. Although no known exploits have been reported in the wild yet, the ease of exploitation and critical impact make this a significant threat. The lack of a vendor project or product name beyond the Tenda i9 router limits detailed attribution, but the vulnerability clearly affects this specific router model and firmware version. The absence of available patches at the time of publication increases the urgency for mitigation.

For European organizations, the impact of this vulnerability can be substantial. Routers like the Tenda i9 are often used in small to medium-sized enterprises (SMEs) and home office environments, which may lack robust network security measures. Exploitation could lead to unauthorized access to internal networks, data interception, and disruption of business operations. Confidential information transmitted through the network could be compromised, and attackers could establish persistent footholds for further attacks. Given the critical nature of the vulnerability and the fact that it requires no authentication or user interaction, attackers could automate exploitation at scale, potentially targeting multiple organizations simultaneously. This could be particularly damaging for sectors reliant on secure communications, such as finance, healthcare, and critical infrastructure. Additionally, compromised routers could be enlisted into botnets, amplifying the threat landscape for European networks.

To mitigate this vulnerability, European organizations should first identify any deployment of Tenda i9 routers running firmware version 1.0.0.8(3828). Immediate steps include isolating affected devices from critical network segments and restricting remote management access to trusted IPs only. Network administrators should monitor network traffic for unusual command execution patterns or unexpected outbound connections originating from these routers. Since no official patches are currently available, organizations should consider temporary mitigations such as disabling vulnerable services or functions if possible. Employing network segmentation and implementing strict firewall rules can limit the attack surface. Additionally, organizations should engage with Tenda support channels to obtain firmware updates or advisories. Regularly updating router firmware once patches are released is critical. Finally, incorporating intrusion detection systems (IDS) and endpoint detection and response (EDR) solutions can help detect and respond to exploitation attempts promptly.