CVE-2026-2202 is a buffer overflow vulnerability identified in the Tenda AC8 router firmware version 16.03.33.05. The flaw resides in the fromSetWifiGusetBasic function within the httpd component, which processes requests to the /goform/WifiGuestSet endpoint. Specifically, the vulnerability is triggered by manipulating the shareSpeed argument, which is not properly validated or bounded, resulting in a buffer overflow condition. This flaw can be exploited remotely by an unauthenticated attacker without requiring user interaction, making it highly accessible. The buffer overflow could allow an attacker to execute arbitrary code on the device, potentially leading to full compromise of the router. This includes the ability to intercept or manipulate network traffic, disrupt network availability, or pivot to internal networks. The CVSS 4.0 score is 8.7 (high), reflecting the ease of exploitation (network vector, low complexity, no privileges or user interaction required) and the severe impact on confidentiality, integrity, and availability. Although no exploits are currently observed in the wild, the public availability of exploit code increases the likelihood of imminent attacks. The vulnerability affects a widely deployed consumer and small business router model, which may be present in many European organizations’ network environments. The lack of an official patch link indicates that mitigation options may be limited or require vendor engagement. This vulnerability underscores the importance of securing network edge devices and monitoring for anomalous activity targeting router management interfaces.

For European organizations, exploitation of CVE-2026-2202 could have significant consequences. Compromise of Tenda AC8 routers could lead to unauthorized access to internal networks, interception or manipulation of sensitive data, and disruption of network services. This is particularly critical for organizations relying on these routers for internet connectivity or guest Wi-Fi access, including small and medium enterprises, educational institutions, and public venues. The ability to execute code remotely without authentication increases the risk of widespread attacks, potentially enabling attackers to establish persistent footholds or launch further attacks within corporate networks. Given the router’s role as a network gateway, attackers could intercept confidential communications or disrupt availability, impacting business operations and data privacy compliance obligations under regulations such as GDPR. The public availability of exploit code further elevates the threat level, necessitating urgent attention to mitigate risks.

1. Immediate mitigation should focus on isolating affected Tenda AC8 devices from untrusted networks, especially restricting access to the /goform/WifiGuestSet endpoint via firewall rules or network segmentation. 2. Disable remote management interfaces on the router if not strictly necessary to reduce exposure. 3. Monitor network traffic for unusual requests targeting the vulnerable endpoint or anomalous behavior indicative of exploitation attempts. 4. Engage with Tenda support or official channels to obtain firmware updates or patches addressing this vulnerability; if unavailable, consider upgrading to newer, supported hardware models. 5. Implement network-level intrusion detection/prevention systems (IDS/IPS) with signatures to detect exploitation attempts. 6. Enforce strong network access controls and limit guest Wi-Fi capabilities to minimize attack surface. 7. Conduct regular security audits of network devices and maintain an inventory to identify vulnerable equipment. 8. Educate IT staff on this vulnerability and ensure incident response plans include scenarios involving router compromise.