CVE-2026-3377 identifies a buffer overflow vulnerability in the Tenda F453 router firmware version 1.0.0.3. The vulnerability resides in the fromSafeUrlFilter function located in the /goform/SafeUrlFilter endpoint. Specifically, the issue arises when the 'page' argument is manipulated by an attacker, causing a buffer overflow condition. Buffer overflows occur when data exceeds the allocated buffer size, leading to memory corruption. This can enable attackers to overwrite critical memory areas, potentially allowing arbitrary code execution or causing the device to crash, resulting in denial of service. The attack vector is remote network access, requiring no authentication or user interaction, which significantly lowers the barrier to exploitation. The CVSS v4.0 score of 8.7 reflects the high impact on confidentiality, integrity, and availability, with low attack complexity and no privileges required. Although no confirmed exploits in the wild are reported, a public exploit is available, increasing the likelihood of active exploitation attempts. The vulnerability affects only firmware version 1.0.0.3, and no patch links are currently provided, indicating that users must rely on vendor updates or mitigations. This vulnerability is critical for environments where Tenda F453 routers are deployed, especially those exposed to untrusted networks or the internet.

The impact of CVE-2026-3377 is significant for organizations using the Tenda F453 router with vulnerable firmware. Successful exploitation can lead to remote code execution, allowing attackers to take full control of the device. This compromises the confidentiality of network traffic, integrity of device configurations, and availability of network services. Attackers could use the compromised router as a foothold to launch further attacks within the internal network, intercept sensitive communications, or disrupt network connectivity. The lack of authentication and user interaction requirements increases the risk of automated exploitation and worm-like propagation. Organizations with internet-facing Tenda F453 devices are particularly vulnerable to attacks that could result in data breaches, network outages, or inclusion in botnets. The absence of an official patch at the time of disclosure further exacerbates the risk, making timely mitigation critical to prevent exploitation.

To mitigate CVE-2026-3377, organizations should first identify all Tenda F453 routers running firmware version 1.0.0.3 within their environment. Until an official patch is released, network administrators should restrict access to the /goform/SafeUrlFilter endpoint by implementing firewall rules or access control lists (ACLs) to block external and untrusted internal network traffic to the device's management interface. Disabling remote management features on the router can reduce exposure. Monitoring network traffic for unusual requests targeting the vulnerable endpoint can help detect exploitation attempts. Employing network segmentation to isolate vulnerable devices from critical infrastructure limits potential lateral movement. Organizations should engage with Tenda support channels to obtain firmware updates or advisories and apply patches promptly once available. Additionally, consider replacing affected devices with models that have active security support if patching is not feasible. Regularly updating router firmware and maintaining an inventory of network devices will aid in proactive vulnerability management.