Not only a mere natural science-biological problem, but human mobility is also the root cause of the spread of the Covid-19 virus. The study of Anthropology of Infection Disease written by Merrill Singer confirms that disease transmission is no longer a question of natural causal biological aspects. Still, it is also tied to human socio-cultural systems, including human mobility activities in Hulu Sembakung North Borneo. Kathleen Coyne Kelly's critique of the study of mobility in “Mapping the mobility of the Plague” makes me, as a social researcher, warn to avoid getting caught up in capturing cultural phenomena that are mono-fragmented in mobile materiality. So Latour's Actor-Network Theory (ANT) analysis can solve the paradox-static problem of mobile materiality entities. The cyclical rite of Tempayan in Hulu Sembakung became an “intermediary” for the mobility of cross-border communities that revived Covid-19 into moving materiality. The Sembakung River, which flows through the Sabah region of Malaysia-North Kalimantan Indonesia, is the main route for community movements to carry out the rites uncontrolled from surveillance, which has resulted in the materiality of the virus moving freely without any “state control”. Therefore, using the ethnographic method and the ANT analysis, this article will describe cross-border rites during the Covid-19 pandemic second wave and quality-measure the function of Covid-19 security control at nation-borders. The final analysis shows traditional rituals become “intermediary”—vehicles for cross-border mobility of the Hulu Sembakung community, which are “tolerated” by the state without any Covid-19 checks and control. This permeates people's mobility risks spreading the virus beyond state control due to the two countries' lack of data recording on cross-border mobility.