CVE-2023-26978 in A7100RU
Summary
by MITRE • 04/07/2023
TOTOlink A7100RU V7.4cu.2313_B20191024 was discovered to contain a command injection vulnerability via the pppoeAcName parameter at /setting/setWanIeCfg.
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Analysis
by VulDB Data Team • 11/13/2025
The vulnerability identified as CVE-2023-26978 represents a critical command injection flaw within the TOTOlink A7100RU router firmware version V7.4cu.2313_B20191024. This issue resides in the web interface configuration handler at the specific endpoint /setting/setWanIeCfg where the pppoeAcName parameter is processed without adequate input validation or sanitization. The vulnerability stems from improper handling of user-supplied data that flows directly into system command execution contexts, creating a pathway for malicious actors to inject arbitrary commands into the underlying operating system.
This command injection vulnerability operates at the application layer and presents a significant risk due to the privileged execution context in which the affected router operates. The pppoeAcName parameter is typically used to configure the Access Concentrator name for PPPoE connections, but the lack of proper input validation allows attackers to append malicious command sequences that will be executed with the privileges of the web server process. This creates a potential for remote code execution on the device, enabling attackers to gain full control over the router's functionality and potentially compromise the entire network infrastructure.
The operational impact of this vulnerability extends beyond simple command execution, as it can be leveraged to establish persistent access, modify network configurations, redirect traffic, or even facilitate lateral movement within a network. The vulnerability affects the router's web administration interface, making it accessible to remote attackers without requiring physical access or authentication credentials. According to CWE classification, this represents a CWE-77 command injection weakness that allows attackers to execute arbitrary commands on the target system, while the ATT&CK framework would categorize this under T1059.001 Command and Scripting Interpreter with specific focus on executing system commands through web interfaces.
Mitigation strategies for this vulnerability should include immediate firmware updates from the vendor to address the input validation deficiencies, network segmentation to limit exposure, and implementation of web application firewalls to monitor and filter suspicious requests. Additionally, network administrators should disable unnecessary web management interfaces, enforce strong authentication mechanisms, and implement regular security assessments to identify similar vulnerabilities in network infrastructure devices. The vulnerability demonstrates the critical importance of input validation and proper sanitization in web applications, particularly in network devices where the attack surface can directly impact network security and integrity.