An OS command injection vulnerability exists in the VPN module of TP-Link Archer AX12 v1, AX17 v1. AX18 v1, and AX1300 v1.6 routers. This vulnerability allows an adjacent, authenticated attacker to execute arbitrary commands on the device by importing a specially crafted VPN client configuration file. The issue stems from improper filtering of special characters.  Successful exploitation of this vulnerability may enable an attacker to gain full control of the affected device, potentially compromising configuration integrity, network security, and service availability.