Booter via un Live CD ou un mode Rescue puis :

mkdir /tmp/boot /tmp/temp
mount /dev/sda5 /tmp/boot
cd /tmp/boot
cp state.tgz /tmp/temp
cd /tmp/temp
tar -xf state.tgz
tar -xf local.tgz
rm -f *.tgz
cd etc
vi shadow (supprimer le hash du password)
cd ..
tar -cf local.tgz etc/
tar -cf state.tgz local.tgz
mv state.tgz /tmp/boot
umount /tmp/boot
reboot