CVE-2022-25455 in AC6
Summary
by MITRE • 03/19/2022
Tenda AC6 v15.03.05.09_multi was discovered to contain a stack overflow via the list parameter in the SetIpMacBind function.
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Analysis
by VulDB Data Team • 03/23/2022
The vulnerability identified as CVE-2022-25455 affects the Tenda AC6 router model with firmware version v15.03.05.09_multi and represents a critical stack overflow flaw within the device's web interface functionality. This issue manifests through the SetIpMacBind function which processes incoming requests containing a list parameter, creating an exploitable condition that can be leveraged by remote attackers to execute arbitrary code on the affected device. The vulnerability stems from inadequate input validation and buffer management within the router's embedded web server implementation, specifically in how it handles user-supplied data during the IP-MAC binding configuration process. Such stack overflow conditions typically occur when the application writes more data to a fixed-length buffer than it can accommodate, causing adjacent memory to be overwritten and potentially leading to complete system compromise.
The technical exploitation of this vulnerability follows established patterns for stack-based buffer overflows that align with CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows attackers to overwrite stack data. The attack vector is remote and requires no authentication, making it particularly dangerous as it can be exploited from outside the local network. The SetIpMacBind function processes network configuration parameters that are passed through the web interface, and when the list parameter exceeds the allocated buffer size, the overflow can corrupt return addresses, function pointers, and other critical stack data. This type of vulnerability directly maps to ATT&CK technique T1210, which covers exploitation of remote services through buffer overflow attacks, and can be classified under the broader category of T1068, which involves exploiting vulnerabilities in software applications.
The operational impact of CVE-2022-25455 extends beyond simple remote code execution, as it can provide attackers with complete control over the affected router's operations. Successful exploitation can enable attackers to modify network configurations, redirect traffic through malicious proxies, install persistent backdoors, or use the compromised device as a pivot point for attacking other systems within the local network. The router's role as a gateway device makes it a prime target for attackers seeking to establish persistent access to corporate or residential networks, potentially leading to data exfiltration, man-in-the-middle attacks, or further network infiltration. Additionally, the vulnerability can be exploited to gain access to sensitive configuration data stored on the device, including credentials for the router's administrative interface and potentially other networked systems that rely on the router for connectivity.
Mitigation strategies for this vulnerability require immediate firmware updates from Tenda to address the underlying buffer overflow condition through proper input validation and bounds checking. Network administrators should implement network segmentation and access controls to limit the potential impact of exploitation, while also monitoring for unusual network traffic patterns that might indicate compromise. The implementation of intrusion detection systems can help identify exploitation attempts targeting this specific vulnerability, and organizations should consider disabling unnecessary web management interfaces when possible. Regular security assessments of network infrastructure should include verification of firmware versions and patch status for all network devices, as this vulnerability demonstrates the importance of maintaining up-to-date firmware to protect against known exploits. The vulnerability also underscores the need for secure coding practices in embedded systems and highlights the importance of input validation as a fundamental security control to prevent buffer overflow conditions.