Background: Distrust of COVID-19 vaccines may hamper vaccination campaigns. We focused on the cognitive determinants of intentions to get vaccinated against COVID-19. We were interested in (i) the effects of stress, and (ii) the effects of self-protection systems on attitudes and intentions to get vaccinated with a COVID-19 vaccine. Methods: We conducted an online observational study with 203 French students (MAge = 19, SDAge = 2.52, Women = 173), in which we measured, through self-reported questionnaires, their perceived stress and vulnerability to disease, belief in a dangerous world, pandemic-related stressors living conditions, attitudes and intentions to get vaccinated, and confidence in the government's management of COVID-19. We conducted two multiple linear mediation analyses.Results: Participants who reported higher trust in the government and who reported higher stress levels were more likely to have positive attitudes toward the COVID-19 vaccine, although both these influences seem to be –at least partially - independent. Conclusions: The factor that most robustly predicted both attitudes and intentions to vaccinate was confidence in the information provided by the government and its ability to manage the pandemic in general. Our analyses suggest the existence of two profiles of people likely to have positive attitudes toward vaccination: those who trust the government and are not stressed by vaccination, and those who do not trust the government but would get vaccinated to reduce their stress. We discuss how to improve the effectiveness of COVID-19 vaccine policies through communication.