CVE-2024-42980 is a stack overflow vulnerability identified in the Tenda FH1206 router firmware version v02.03.01.35. The vulnerability arises from improper handling of the 'page' parameter within the frmL7ImForm function. When an attacker sends a specially crafted POST request containing malicious input in this parameter, it triggers a stack overflow condition. This overflow can corrupt the execution stack, leading to a crash of the router's firmware process and resulting in a Denial of Service (DoS) state where the device becomes unresponsive or reboots. The vulnerability requires no authentication or user interaction, making it remotely exploitable by any attacker with network access to the device. The CVSS v3.1 base score is 7.5, reflecting high severity due to the ease of exploitation (network vector, low attack complexity) and the impact on availability (complete DoS). The vulnerability is categorized under CWE-400 (Uncontrolled Resource Consumption), indicating that the overflow causes resource exhaustion or instability. No patches or firmware updates have been released at the time of publication, and no known exploits have been observed in the wild. The affected device is a widely deployed consumer router, often used in home and small office environments, which could be targeted to disrupt internet connectivity or as part of larger network attacks.

The primary impact of CVE-2024-42980 is the disruption of network availability due to the Denial of Service condition it causes. Organizations relying on Tenda FH1206 routers may experience network outages, loss of internet connectivity, and interruption of critical services dependent on these devices. This can affect both home users and small businesses, potentially leading to operational downtime and productivity loss. In larger network environments, compromised routers could be used as entry points for further attacks or to degrade network infrastructure. Although the vulnerability does not allow for data theft or code execution, the loss of availability can have cascading effects on business continuity and user experience. The lack of authentication requirement and ease of exploitation increase the risk of widespread attacks, especially if automated scanning tools target these devices. The absence of patches further elevates the threat level until mitigations are applied.

1. Immediately identify and inventory all Tenda FH1206 routers within the network environment. 2. Restrict network access to the router's management interface by implementing firewall rules that limit access to trusted IP addresses only. 3. Disable remote management features if not required to reduce exposure to external attackers. 4. Monitor network traffic for unusual POST requests targeting the 'page' parameter or abnormal router behavior indicative of DoS attempts. 5. Employ network intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics to detect exploitation attempts targeting this vulnerability. 6. Contact Tenda support or monitor official channels for firmware updates or patches addressing CVE-2024-42980 and apply them promptly once available. 7. As a temporary measure, consider replacing vulnerable devices with alternative hardware not affected by this vulnerability in critical environments. 8. Educate users and administrators about the risk and signs of exploitation to enable rapid response.