# Offensive Container Escape

Container escape and breakout techniques targeting Docker, containerd, and Podman...

- Repository: https://github.com/SnailSploit/Claude-Red (10186 stars)
- Category: Security
- License: MIT
- Last updated: 2026-10-12
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add SnailSploit/Claude-Red --skill offensive-container-escape -g -a claude-code -y`
Codex: `npx skills add SnailSploit/Claude-Red --skill offensive-container-escape -g -a codex -y`
Cursor: `npx skills add SnailSploit/Claude-Red --skill offensive-container-escape -g -a cursor -y`
Gemini CLI: `npx skills add SnailSploit/Claude-Red --skill offensive-container-escape -g -a gemini-cli -y`

## Description

Container escape and breakout techniques targeting Docker, containerd, and Podman runtimes. Covers privileged container breakout via host filesystem mount and nsenter, Docker socket abuse through /var/run/docker.sock, Linux capability exploitation including CAP_SYS_ADMIN, CAP_SYS_PTRACE, and CAP_NET_ADMIN, cgroup v1 notify_on_release escape, runc CVEs such as CVE-2019-5736 and CVE-2024-21626 Leaky Vessels, kernel exploits from within containers, and Dockerfile misconfigurations like --privileged and host namespace sharing. Includes enumeration with capsh, amicontained, deepce, CDK, and nsenter. Maps to MITRE ATT&CK T1611 Escape to Host. Use this skill when the engagement scope includes container breakout, Docker escape, container privilege escalation, host access from container, or when you land inside a containerized environment and need to reach the underlying host.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Container Escape and Breakout

You have a shell inside a container. Your objective is to break out to the underlying host operating system. Container isolation relies on Linux namespaces, cgroups, seccomp profiles, AppArmor/SELinux, and dropped capabilities. Every misconfiguration in these layers is an escape vector. This skill walks you through systematic enumeration, exploitation of common misconfigurations, abuse of exposed runtime sockets, capability-based escapes, cgroup breakouts, and known CVEs against container runtimes.

## Quick Workflow

1. Confirm you are inside a container (check for `.dockerenv`, cgroup entries, PID 1 process).
2. Enumerate capabilities, mounts, namespaces, and sockets with automated tools.
3. Identify the escape vector: privileged mode, socket exposure, dangerous capabilities, cgroup misconfiguration, or vulnerable runtime.
4. Execute the breakout technique matching the vector.
5. Validate host access by reading `/etc/hostname`, checking PID namespace, or writing to host filesystem.
6. Pivot from host access to lateral movement across the cluster or infrastructure.

---

## Phase 1: Container Detection and Enumeration

Before attempting escape, confirm you are containerized and map the attack surface.

### Detecting Container Environment

```bash
# Check for Docker marker file
ls -la /.dockerenv

# Check cgroup entries for container identifiers
cat /proc/1/cgroup | grep -E 'docker|containerd|kubepods|podman'

# Check PID 1 process (containers typically run app process, not init)
cat /proc/1/cmdline | tr '\0' ' '

# Check for container-specific environment variables
env | grep -iE 'kubernetes|docker|container|pod'

# Check hostname (often a truncated container ID)
hostname

# Check mount info for overlay filesystem
cat /proc/1/mountinfo | head -20
```

### Automated Enumeration Tools

The rest: https://github.com/SnailSploit/Claude-Red/blob/HEAD/Skills/container/offensive-container-escape/SKILL.md