CVE-2022-44843 in A7100RU
Summary
by MITRE • 11/25/2022
TOTOlink A7100RU V7.4cu.2313_B20191024 was discovered to contain a command injection vulnerability via the port parameter in the setting/setOpenVpnClientCfg function.
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Analysis
by VulDB Data Team • 12/23/2022
The vulnerability identified as CVE-2022-44843 affects the TOTOlink A7100RU router model running firmware version V7.4cu.2313_B20191024 and represents a critical command injection flaw within the device's web management interface. This vulnerability resides in the setting/setOpenVpnClientCfg function where the port parameter is improperly handled, allowing attackers to execute arbitrary commands on the affected device with the privileges of the web server process. The issue stems from insufficient input validation and sanitization of user-supplied parameters, creating a direct pathway for malicious command execution that bypasses normal authentication mechanisms. The vulnerability is particularly concerning as it affects a widely deployed consumer-grade router model that typically operates in unsecured network environments.
The technical exploitation of this vulnerability occurs through manipulation of the port parameter within the setOpenVpnClientCfg API endpoint, which processes OpenVPN client configuration settings. When an attacker submits malicious input through this parameter, the system fails to properly sanitize the input before incorporating it into system commands, leading to arbitrary code execution. This command injection vulnerability falls under the CWE-77 category of Command Injection, specifically manifesting as a weakness in how the application handles external input during command construction. The vulnerability enables attackers to execute system commands with the privileges of the web server process, potentially allowing full system compromise including access to network resources, modification of routing configurations, and establishment of persistent backdoors.
The operational impact of this vulnerability extends beyond simple unauthorized access as it provides attackers with complete control over the affected router's functionality. An attacker could leverage this vulnerability to redirect network traffic through malicious proxies, establish unauthorized VPN connections, modify firewall rules, or even install malware on the device. The affected TOTOlink A7100RU router serves as a potential entry point for broader network infiltration, particularly in environments where the device serves as a gateway or firewall component. Given that the vulnerability exists in the web management interface, it can be exploited remotely without requiring physical access to the device, making it particularly dangerous for both home and enterprise deployments. The compromised router could also be used as a pivot point for attacking other devices within the local network segment.
Mitigation strategies for CVE-2022-44843 should prioritize immediate firmware updates from the vendor, as the vulnerability affects a specific firmware version that likely contains a patch. Network administrators should implement strict network segmentation and monitor for unusual traffic patterns that might indicate exploitation attempts. Additional protective measures include disabling unnecessary web management interfaces, implementing strong access controls with complex authentication, and deploying intrusion detection systems to monitor for suspicious API calls targeting the vulnerable setOpenVpnClientCfg endpoint. The vulnerability aligns with ATT&CK technique T1059.001 for Command and Scripting Interpreter, specifically focusing on the execution of system commands through web interfaces. Organizations should also consider implementing network access controls that restrict direct access to router management interfaces from external networks, and maintain detailed logging of all configuration changes to detect potential exploitation attempts.