Summary
A critical OS command injection vulnerability affects the CGI handler of Netcore NR289-GE 1.4.5102. The ntp_ip argument in /set_ntp_server_ip.cgi can be manipulated so that commands are executed by the device.
Because the affected function is remotely reachable, an attacker who can access the CGI endpoint may execute commands in the device's operating-system context. Public exploit availability increases the risk of active exploitation.
Affected context
The issue occurs in Netcore NR289-GE 1.4.5102 deployments where the CGI handler exposes /set_ntp_server_ip.cgi and processes the ntp_ip parameter. Risk depends on network reachability, access controls, and the privileges available to the web or CGI service when it invokes system functionality.
Exploit preconditions
- Attack surface: Network-accessible CGI handler on the affected device
- Required access: Ability to send requests to
/set_ntp_server_ip.cgi; authentication requirements depend on the device's configuration - Trigger point: Processing of the
ntp_ipargument by thesystemfunction - Why exploitation is possible: Input is incorporated into an operating-system command without sufficient separation or validation, allowing command syntax to influence execution
Why this happens
The vulnerability results from passing attacker-influenced input to an operating-system command through a shell or command execution interface. When metacharacters or command structure are not safely constrained, data is interpreted as executable logic rather than only as an NTP server address.
This maps primarily to CWE-78: Improper Neutralization of Special Elements used in an OS Command, with CWE-77: Improper Neutralization of Special Elements in Output Used by a Downstream Component representing the broader command-injection class.
Potential impact
- An attacker may execute arbitrary commands on the network device
- Device configuration or routing behavior could be modified
- Credentials, network information, or stored data could be exposed
- The device could be used for network reconnaissance or lateral movement
- Availability could be reduced through service disruption or destructive commands
General mitigation guidance
Mitigation generally focuses on removing shell interpretation from the request-processing path and reducing trust in network-provided values.
Common defensive patterns include:
- Use structured process-execution APIs that do not invoke a shell
- Apply strict allowlist validation for IP address and hostname formats
- Pass validated values as separate arguments rather than concatenated command strings
- Reject unexpected encodings, delimiters, whitespace, and command-control characters
- Run CGI functionality with the minimum privileges required
- Restrict administrative interfaces to trusted management networks
- Apply network segmentation and disable unnecessary remote management exposure
How teams detect issues like this
Organizations can look for command-injection risks through:
- Static analysis rules identifying
system, shell execution, or command-construction APIs receiving request parameters - Code review checks for string concatenation or interpolation into operating-system commands
- Tests that verify strict parsing and rejection of malformed NTP address values
- Web-server and device logs containing unusual
ntp_ipvalues, shell metacharacters, or unexpected command syntax - Network monitoring for anomalous outbound connections or administrative activity from the device
- Policy enforcement requiring shell-free process execution and allowlist validation for CGI inputs
Automated security scanning and code-review tools may help identify similar input-to-command data flows.
