CVE-2026-3274 identifies a critical buffer overflow vulnerability in the Tenda F453 router firmware version 1.0.0.3. The vulnerability resides in the frmL7ProtForm function within the httpd component, which processes requests to the /goform/L7Prot endpoint. Specifically, the flaw arises from improper handling of the 'page' argument, allowing an attacker to overflow a buffer by sending crafted HTTP requests. This buffer overflow can corrupt memory, potentially enabling remote code execution or denial of service conditions. The attack vector is network-based and does not require authentication or user interaction, making it highly exploitable remotely. The vulnerability has a CVSS 4.0 base score of 8.7, reflecting its high impact on confidentiality, integrity, and availability, with low attack complexity and no privileges or user interaction needed. Although no active exploitation has been reported, the public release of exploit code significantly raises the threat level. The affected product, Tenda F453, is a consumer-grade router commonly used in home and small office environments, exposing a broad user base to risk. The lack of an official patch at the time of disclosure necessitates immediate mitigation efforts to prevent exploitation. This vulnerability underscores the importance of secure input validation in embedded device web interfaces and the risks posed by exposed management endpoints.

The impact of CVE-2026-3274 is substantial for organizations and individuals using the Tenda F453 router. Exploitation can lead to remote code execution, allowing attackers to gain control over the device, manipulate network traffic, intercept sensitive data, or disrupt network availability. This compromises the confidentiality, integrity, and availability of the network environment. For home users, this could mean unauthorized access to personal data and network resources. For small businesses relying on these routers, the threat extends to potential business disruption and data breaches. The ease of remote exploitation without authentication increases the likelihood of widespread attacks, especially given the public availability of exploit code. Additionally, compromised routers can be leveraged as footholds for lateral movement within networks or as part of botnets for larger scale attacks. The absence of a patch at disclosure time heightens the urgency for risk mitigation. Overall, the vulnerability poses a critical risk to network security and operational continuity for affected users worldwide.

1. Immediate mitigation should focus on restricting access to the router's management interface, especially the /goform/L7Prot endpoint, by implementing network-level controls such as firewall rules or access control lists to limit exposure to trusted IP addresses only. 2. Disable remote management features on the Tenda F453 router if not strictly necessary to reduce the attack surface. 3. Monitor network traffic for unusual or malformed HTTP requests targeting the vulnerable endpoint to detect potential exploitation attempts. 4. Regularly check for firmware updates from Tenda and apply patches promptly once available to remediate the vulnerability. 5. Consider deploying network intrusion detection or prevention systems (IDS/IPS) with signatures targeting this specific exploit to block or alert on attack attempts. 6. For organizations, segment networks to isolate vulnerable devices from critical infrastructure and sensitive data. 7. Educate users about the risks of using outdated firmware and the importance of timely updates. 8. If patching is delayed, consider temporary replacement of vulnerable devices with models not affected by this vulnerability to maintain security posture.