CVE-2022-35557 in Tenda
Summary
by MITRE • 08/12/2022
A stack overflow vulnerability exists in /goform/wifiSSIDget 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.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 09/10/2022
The stack overflow vulnerability identified in CVE-2022-35557 affects the Tenda W6 router firmware version W6 V1.0.0.9(4122) and specifically targets the /goform/wifiSSIDget endpoint. This vulnerability resides within the web interface form handling mechanism where the index parameter is processed without adequate input validation or bounds checking. The flaw represents a classic buffer overflow condition that occurs when the system attempts to write data beyond the allocated stack memory space, creating a potential exploitation vector for malicious actors seeking to disrupt service availability.
The technical implementation of this vulnerability stems from improper parameter handling within the firmware's web form processing logic. When an attacker submits a malformed index parameter to the /goform/wifiSSIDget endpoint, the system fails to validate the input length against the predetermined buffer size allocated on the stack. This condition allows for memory corruption that can lead to arbitrary code execution or complete system crash. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and demonstrates how insufficient input validation creates exploitable conditions in embedded systems. The attack surface is particularly concerning given that the vulnerability exists in a web-based management interface that is commonly accessible to network users.
From an operational perspective, this vulnerability presents a significant denial of service risk to affected Tenda W6 devices. Attackers can reliably trigger the stack overflow by crafting malicious requests to the specific endpoint, resulting in immediate service disruption and potential system reboot cycles. The impact extends beyond simple availability issues as the vulnerability could potentially be leveraged for more sophisticated attacks if combined with other exploitation techniques. The nature of the flaw means that any network-connected device running the vulnerable firmware version becomes immediately susceptible to exploitation, making it a high-priority concern for network administrators managing these devices. This vulnerability also aligns with ATT&CK technique T1499.004, which covers network denial of service attacks, and represents a critical weakness in the device's defensive posture.
The recommended mitigation strategy involves immediate firmware updates from Tenda to address the buffer overflow condition through proper input validation and bounds checking mechanisms. Network administrators should implement network segmentation and access controls to limit exposure of affected devices to untrusted networks, while also monitoring for suspicious traffic patterns that may indicate exploitation attempts. Additionally, implementing intrusion detection systems capable of identifying malformed requests to the vulnerable endpoint can provide early warning of attempted exploitation. The vulnerability underscores the importance of secure coding practices in embedded firmware development and highlights the necessity of comprehensive security testing for network infrastructure devices. Organizations should also consider implementing network monitoring solutions that can detect and alert on abnormal behavior patterns associated with DoS attacks targeting web management interfaces.