man 5 sudoers
informa que existe uma opção timestamp_timeout
:
timestamp_timeout
Number of minutes that can elapse before sudo will ask for a passwd again. The timeout may include a fractional component if minute granularity is insufficient, for example 2.5. The default is 5. Set this to 0 to always prompt for a password. If set to a value less than 0 the user’s time stamp will never expire. This can be used to allow users to create or delete their own time stamps via “sudo -v” and “sudo -k” respectively.
Então, sim, ele pode ser configurado via /etc/sudoers
e, por padrão, expira após 5 minutos.