container-trust-boundary SKILL.md skillA
container-trust-boundary from annatchijova/skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add annatchijova/skills/container-trust-boundary@git:20260825.8500180Pins git:20260825.8500180 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- annatchijova/skills
- Path
container-trust-boundary/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260825.8500180, committed Aug 25, 2026
- Size
- 8,018 bytes
- Repository stars
- 9
- License
- a license file GitHub does not identify
Treat a container as isolation, not as a security boundary — because "it runs in a container" is not "it is contained": it shares the host kernel, and the real perimeter is the kernel attack surface it can reach, the provenance of the image it was built from, the orchestration identity it holds, and the escape surface it was granted. Use whenever the system is Docker/Kubernetes/containerd and the question is blast radius, isolation, or "is this safe to run": a compromised or untrusted…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Container Trust Boundary A container is a bundle of namespaces and cgroups sharing one host kernel. That is isolation — process A cannot see process B's filesystem — and it is emphatically not a security boundary in the sense a VM or a hypervisor is. "It runs in a container" is a statement about tidiness, not containment, and every threat model that stops at the container edge has drawn its perimeter one layer too shallow. The boundary that actually matters is four things behind the edge, each of which a "contained" workload can reach: - **The shared kernel** — one exploitable kernel bug and namespaces are a suggestion, not a wall. The container's real attack surface includes every syscall it can make. - **The image's provenance** — the code was decided at build time by whoever authored the layers and the base image. An unpinned `FROM ...:latest` from an unverified registry is untrusted code you scheduled with intent. - **The identity it holds** — a Kubernetes pod carries a service-account token; that token is a control-plane credential (see `cloud-control-plane-reasoning`). The pod does not need to escape the node if its token already reaches the API server. …
Read the whole file at its exact version.
How to install
mdr add annatchijova/skills/container-trust-boundary@sha256:257c0c9b36260d24The line at the top of this page pins the label git:20260825.8500180, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_7cmzlbh3njntp5y3)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Aug 25, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (8018 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
annatchijova/skills · 9 stars · license a license file GitHub does not identify · pushed 2026-11-02 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_7cmzlbh3njntp5y3 GET https://markdownregistry.com/api/v1/resolve?ref=annatchijova/skills/container-trust-boundary GET https://markdownregistry.com/api/v1/blob/257c0c9b36260d247ddd58810f0e9fab956d2bcfbdcb2e92d136524e8687156f
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.