RIOT is a real-time multi-threading operating system that supports a range of devices that are typically 8-bit, 16-bit and 32-bit microcontrollers. The size check in the `gcoap_dns_server_proxy_get()` function contains a small typo that may lead to a buffer overflow in the subsequent `strcpy()`. In detail, the length of the `_uri` string is checked instead of the length of the `_proxy` string. The `_gcoap_forward_proxy_copy_options()` function does not implement an explicit size check before copying data to the `cep->req_etag` buffer that is `COAP_ETAG_LENGTH_MAX` bytes long. If an attacker can craft input so that `optlen` becomes larger than `COAP_ETAG_LENGTH_MAX`, they can cause a buffer overflow. If the input above is attacker-controlled and crosses a security boundary, the impact of th