CVE-2017-18368 in P660HN-T1A
Summary
by MITRE
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by TrueOnline has a command injection vulnerability in the Remote System Log forwarding function, which is accessible by an unauthenticated user. The vulnerability is in the ViewLog.asp page and can be exploited through the remote_host parameter.
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Analysis
by VulDB Data Team • 07/04/2025
The CVE-2017-18368 vulnerability represents a critical command injection flaw in ZyXEL P660HN-T1A v1 routers running firmware versions up to 7.3.15.0 v001. This vulnerability specifically affects the Remote System Log forwarding functionality that is accessible to unauthenticated users through the ViewLog.asp web interface page. The flaw is particularly concerning as it allows remote attackers to execute arbitrary commands on the affected device without requiring any authentication credentials. The vulnerability manifests through the remote_host parameter which is improperly validated and sanitized, creating an exploitable entry point for malicious actors. This issue impacts routers distributed by TrueOnline and demonstrates the widespread nature of command injection vulnerabilities in network device firmware implementations.
The technical exploitation of this vulnerability stems from insufficient input validation within the ViewLog.asp page implementation. When the remote_host parameter is processed, the system fails to properly sanitize user-supplied input, allowing attackers to inject malicious commands that are subsequently executed within the router's command execution context. This represents a classic command injection vulnerability categorized under CWE-77, which occurs when a program constructs command strings using externally-influenced input without proper validation or sanitization. The vulnerability is particularly dangerous because it operates at the system level, potentially enabling attackers to gain full administrative control over the device and access sensitive network information or functionality.
The operational impact of CVE-2017-18368 extends beyond simple unauthorized access, as it provides attackers with the capability to execute arbitrary code with the privileges of the web server process running on the router. This could enable attackers to modify network configurations, redirect traffic, install malware, or establish persistent backdoors within the network infrastructure. The vulnerability's accessibility to unauthenticated users means that any individual with network access can potentially exploit this flaw, making it a significant risk for enterprise and home network environments. From an attacker's perspective, this vulnerability aligns with ATT&CK technique T1059.001 for command and scripting interpreter, allowing for execution of malicious commands through the affected web interface. The implications for network security are severe as compromised routers can serve as launching points for further attacks against internal network resources.
Mitigation strategies for CVE-2017-18368 should prioritize immediate firmware updates from ZyXEL to address the command injection vulnerability. Network administrators should implement network segmentation and access controls to limit exposure of affected devices to untrusted networks. The use of network monitoring tools to detect anomalous traffic patterns related to log forwarding activities can help identify potential exploitation attempts. Additionally, implementing web application firewalls and input validation measures can provide additional protection layers. Organizations should also consider disabling the Remote System Log forwarding functionality entirely if it is not required for operations, as this removes the attack surface. Regular security assessments and vulnerability scanning should be conducted to identify similar issues in other network infrastructure devices, as command injection vulnerabilities are commonly found in embedded systems and network appliances. The vulnerability demonstrates the critical importance of proper input validation in web applications and highlights the need for robust security practices in firmware development and deployment.