RIOT is an operating system for internet of things (IoT) devices. In version 2024.04 and prior, the function "_parse_advertise", located in "/sys/net/application_layer/dhcpv6/client.c", has no minimum header length check for "dhcpv6_opt_t" after processing "dhcpv6_msg_t". This omission could lead to an out-of-bound read, causing system inconsistency. Additionally, the same lack of a header length check is present in the function "_preparse_advertise", which is called by "_parse_advertise" before handling the request. As of time of publication, no known patched version exists.