Grandstream GWN7660ELR before firmware version 1.0.27.6 contains an information disclosure vulnerability that allows unauthenticated remote attackers to obtain sensitive system information by querying the SNMP v2c service configured with the default community string 'public'. Attackers can query standard MIBs over the SNMP port to retrieve operating system and kernel version, running process names and command-line arguments, network interface configuration, routing table entries, ARP table mappings, active TCP connection details, and file system paths, enabling detailed reconnaissance of the device and adjacent network infrastructure.