RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.04, the ATWINC15x0 driver's _atwinc15x0_sta_set_current_ssid function uses strcpy to copy an SSID without checking the destination size. When MODULE_ATWINC15X0_DYNAMIC_CONNECT is enabled, a nearby attacker can advertise a malformed or oversized SSID that is processed during Wi-Fi scanning, causing memory corruption and potentially a hard fault, denial of service, or code execution. This issue is fixed in version 2026.04.