Main_Analysis_Content.asp in /apply.cgi on ASUS RT-AC66U, RT-AC68U, RT-AC86U, RT-AC88U, RT-AC1900, RT-AC2900, and RT-AC3100 devices before 3.0.0.4.384_10007; RT-N18U devices before 3.0.0.4.382.39935; RT-AC87U and RT-AC3200 devices before 3.0.0.4.382.50010; and RT-AC5300 devices before 3.0.0.4.384.20287 allows OS command injection via the pingCNT and destIP fields of the SystemCmd variable.