CVE-2022-35560 in Tenda
Summary
by MITRE • 08/12/2022
A stack overflow vulnerability exists in /goform/wifiSSIDset in Tenda W6 V1.0.0.9(4122) version, which can be exploited by attackers to cause a denial of service (DoS) via the index parameter.
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Analysis
by VulDB Data Team • 09/10/2022
The vulnerability identified as CVE-2022-35560 represents a critical stack overflow condition within the Tenda W6 router firmware version 1.0.0.9(4122) specifically affecting the /goform/wifiSSIDset endpoint. This flaw resides in the web interface handling mechanism where the index parameter is processed without adequate bounds checking or input validation. The stack overflow occurs when an attacker submits a malformed index value that exceeds the allocated buffer space, causing the program to overwrite adjacent memory locations on the stack. This type of vulnerability falls under CWE-121 Stack-based Buffer Overflow, which is classified as a fundamental memory safety issue that can lead to unpredictable behavior and system instability. The affected device is a wireless router running embedded firmware that processes web form submissions through the goform interface, which is commonly used for device configuration management in consumer and small office networking equipment.
The operational impact of this vulnerability extends beyond simple denial of service conditions as it represents a potential pathway for more sophisticated attacks. When the stack overflow occurs during processing of the index parameter, the router's web server process may crash or behave unpredictably, leading to complete service disruption for network users. The attacker does not require authentication to exploit this vulnerability since the issue exists in the web interface processing layer. This makes the vulnerability particularly dangerous in environments where network availability is critical, as it can be triggered remotely without prior access credentials. The DoS condition can persist until the device is manually rebooted or the firmware is updated, creating extended periods of network disruption that can affect business operations and user connectivity.
From a security perspective, this vulnerability demonstrates poor input validation practices in embedded web applications and highlights the importance of proper memory management in firmware development. The attack surface is limited to the specific web form endpoint but represents a significant risk due to the accessibility of web interfaces on network devices. The vulnerability can be exploited using standard web request manipulation techniques, making it accessible to attackers with basic technical knowledge. According to ATT&CK framework, this vulnerability aligns with T1210 Exploitation of Remote Services and T1499 Endpoint Denial of Service, as it allows for remote service disruption through exploitation of a web application vulnerability. The attack requires no specialized tools beyond standard HTTP request manipulation utilities, making it a particularly concerning flaw in consumer networking equipment where users may not regularly update firmware versions.
Organizations and users should immediately implement mitigations including firmware updates from Tenda if available, network segmentation to limit access to the vulnerable web interface, and monitoring for unusual traffic patterns that may indicate exploitation attempts. The vulnerability underscores the need for regular firmware updates and proper security testing of embedded devices, particularly those with web-based management interfaces. Network administrators should consider disabling unnecessary web management interfaces when possible and implementing access controls to limit who can submit requests to the vulnerable endpoint. The incident serves as a reminder that even consumer-grade networking equipment requires proper security considerations and regular maintenance to prevent exploitation of known vulnerabilities that can lead to significant service disruption and potential compromise of network security posture.