An exploitable buffer overflow vulnerability exists in the samsungWifiScan handler of video-core's HTTP server of Samsung SmartThings Hub STH-ETH-250 - Firmware version 0.20.17. The video-core process incorrectly extracts fields from a user-controlled JSON payload, leading to a buffer overflow on the stack. The strcpy at [8] overflows the destination buffer, which has a size of 40 bytes. An attacker can send an arbitrarily long 'callbackUrl' value in order to exploit this vulnerability.