CVE-2020-23583

Vulnerability

A Remote Code Execution (RCE) vulnerability exists in OPTILINK OP-XT71000N hardware version V2.2 with firmware version OP_V3.3.1-191028. The flaw resides in the /diag_ping_admin.asp page, specifically within the PingTest interface. The application fails to sanitize user-supplied input when passing an IP address to the ping command, allowing an attacker to inject arbitrary operating system commands by appending a pipe character (|) followed by the malicious command [1].

Exploitation

An attacker can exploit this vulnerability by sending a crafted HTTP request to the /diag_ping_admin.asp endpoint. The attacker must provide a payload consisting of a valid IP address followed by a pipe and the desired command (e.g., 8.8.8.8|id). No authentication is required if the interface is exposed; the attacker needs network access to the device's management interface [1]. The exact step involves submitting the command via the PingTest parameter.

Impact

Successful exploitation allows the attacker to execute arbitrary commands on the underlying operating system with the privileges of the web server (often root on embedded devices). This leads to full compromise of the device, including the ability to read sensitive data, modify configurations, install persistent backdoors, or launch further attacks on internal networks [1].

Mitigation

As of the publication date (2022-11-23), no official patch or firmware update from OPTILINK has been publicly released to address this vulnerability. Affected users should isolate the device management interface from untrusted networks (e.g., place behind a firewall and restrict access to trusted IPs) and monitor for vendor updates. The device may be end-of-life; if so, replacement with a supported model is recommended [1].