Can the ADC-V523/523X be used outdoors?

No. The ADC-V523/523X is meant for indoor use only and is not IP rated. The operating temperature is 32°F - 104° F (0°C - 40° C) and the operating humidity is <95% Non-condensing. 

For more information about the ADC-V523/523X, see 1080p Indoor Wi-Fi Camera (ADC-V523/523X) - Data Sheet.