CVE-2026-2180 is a stack-based buffer overflow vulnerability identified in the Tenda RX3 router firmware version 16.03.13.11. The flaw exists in an unspecified function handling the /goform/fast_setting_wifi_set endpoint, specifically when processing the ssid_5g parameter. By crafting a malicious request with a manipulated ssid_5g argument, an attacker can overflow the stack buffer, leading to memory corruption. This corruption can be leveraged to execute arbitrary code remotely on the device with elevated privileges, as no authentication or user interaction is required. The vulnerability has a CVSS 4.0 base score of 8.7, indicating high severity, with an attack vector of network (remote), low attack complexity, no privileges required, and no user interaction needed. The impact metrics indicate high confidentiality, integrity, and availability impacts, meaning an attacker could fully compromise the device, intercept or alter data, and disrupt network operations. Although no known exploits are currently active in the wild, a public exploit is available, increasing the likelihood of exploitation. The vulnerability affects only the specified firmware version, and no official patches have been linked yet. The Tenda RX3 is a widely used consumer and small office router, making this vulnerability significant for home users and small businesses relying on this device for network connectivity and security.

This vulnerability poses a significant risk to organizations and individuals using the Tenda RX3 router with firmware version 16.03.13.11. Successful exploitation can lead to full device compromise, allowing attackers to execute arbitrary code with elevated privileges. This can result in unauthorized access to internal networks, interception and manipulation of network traffic, disruption of network services, and potential pivoting to other internal systems. The confidentiality of sensitive data passing through the router can be compromised, and the integrity and availability of network services can be severely impacted. Given the router's role as a network gateway, exploitation could facilitate broader attacks against connected devices and infrastructure. The availability of a public exploit increases the risk of widespread attacks, especially in environments where firmware updates are not promptly applied. Small businesses and home users may be particularly vulnerable due to limited security monitoring and patch management capabilities.

1. Immediate mitigation involves isolating the affected Tenda RX3 devices from untrusted networks to reduce exposure to remote attacks. 2. Monitor network traffic for unusual activity targeting the /goform/fast_setting_wifi_set endpoint or suspicious ssid_5g parameter usage. 3. Implement network-level protections such as firewall rules to restrict access to the router’s management interfaces from untrusted sources. 4. Disable remote management features if enabled to limit attack surface. 5. Regularly check for and apply official firmware updates from Tenda addressing this vulnerability once released. 6. If patching is delayed, consider replacing affected devices with models not impacted by this vulnerability. 7. Employ network segmentation to limit the impact of a compromised router on critical internal systems. 8. Educate users about the risks and signs of router compromise to enable early detection and response.