CVE-2022-37798 in AC1206
Summary
by MITRE • 08/25/2022
Tenda AC1206 V15.03.06.23 was discovered to contain a stack overflow via the list parameter at the function formSetVirtualSer.
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Analysis
by VulDB Data Team • 10/01/2022
The vulnerability identified as CVE-2022-37798 affects the Tenda AC1206 router firmware version V15.03.06.23 and represents a critical stack overflow condition that can be exploited through the formSetVirtualSer function. This issue manifests when the list parameter is manipulated during the processing of web requests, creating a potential pathway for remote code execution and system compromise. The vulnerability resides within the router's web interface handling mechanism, specifically targeting the stack memory allocation during function execution.
The technical flaw stems from inadequate input validation within the formSetVirtualSer function where the list parameter is processed without proper bounds checking or sanitization. When an attacker crafts malicious input to this parameter, the system fails to properly validate the length and content of the data being passed, allowing the attacker to overflow the allocated stack buffer. This condition creates a classic stack-based buffer overflow scenario that can be leveraged to overwrite return addresses, function pointers, and other critical stack data structures. The vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which occurs when a program writes data to a buffer located on the stack and overflows the buffer's capacity.
The operational impact of this vulnerability extends beyond simple denial of service conditions to encompass full system compromise and potential persistent access. An attacker who successfully exploits this vulnerability could execute arbitrary code with the privileges of the web server process, potentially gaining root access to the router's operating system. This would enable the attacker to modify network configurations, install malicious firmware, redirect traffic, or establish persistence mechanisms within the network infrastructure. The vulnerability is particularly concerning as it affects a consumer-grade wireless router that typically operates in unsecured network environments and may be accessible from external networks.
From an attack perspective, this vulnerability follows the ATT&CK framework's technique T1210 Exploitation of Remote Services, where adversaries target network services to gain unauthorized access. The attack surface is broad as the vulnerability exists in the web interface, making it accessible to remote attackers without requiring physical access or specialized equipment. The exploitation process would involve crafting a malicious HTTP request with oversized list parameter data that triggers the buffer overflow condition. Security professionals should note that this vulnerability could be automatically detected by network scanning tools and may be exploited by automated attack scripts targeting known firmware versions.
Mitigation strategies for CVE-2022-37798 should prioritize immediate firmware updates from Tenda's official website to address the underlying buffer overflow condition. Network administrators should implement network segmentation to limit access to affected devices, disable unnecessary services, and deploy intrusion detection systems to monitor for exploitation attempts. Additionally, implementing proper input validation and boundary checking mechanisms within the web application code would prevent similar vulnerabilities from occurring in future versions. The vulnerability demonstrates the importance of secure coding practices and proper memory management in embedded systems, particularly those exposed to network-based attacks. Organizations should conduct vulnerability assessments of their network infrastructure to identify other potentially affected devices running similar firmware versions and ensure that all network devices receive timely security updates from manufacturers.