WDR201A WiFi Extender (HW V2.1, FW LFMZX28040922V1.02) contains an OS command injection vulnerability in the makeRequest.cgi binary that allows unauthenticated remote attackers to execute arbitrary shell commands by injecting malicious input into the set_time or StartSniffer functions. Attackers can craft a POST request with specially crafted ampersand-delimited parameters to bypass input sanitization and execute commands with a maximum length of 31 bytes through the date command or channel parameter processing.