Systeminformation has a Command Injection via unsanitized interface parameter in wifi.js retry path

Summary

A command injection vulnerability in the wifiNetworks() function allows an attacker to execute arbitrary OS commands via an unsanitized network interface parameter in the retry code path.

Details

In lib/wifi.js, the wifiNetworks() function sanitizes the iface parameter on the initial call (line 437). However, when the initial scan returns empty results, a setTimeout retry (lines 440-441) calls getWifiNetworkListIw(iface) with the original unsanitized iface value, which is passed directly to execSync('iwlist ${iface} scan').

PoC

1. Install systeminformation@5.30.7
2. Call si.wifiNetworks('eth0; id')
3. The first call sanitizes input, but if results are empty, the retry executes: iwlist eth0; id scan

Impact

Remote Code Execution (RCE). Any application passing user-controlled input to si.wifiNetworks() is vulnerable to arbitrary command execution with the privileges of the Node.js process.