SKEL specifies a document format and a plugin system that executes external tools (MUSCLE). Security reports are taken seriously.

• Preferred: GitHub → Security → Report a vulnerability (private advisory) on this repository.
• If private reporting is unavailable to you, open an issue titled [security] without exploit details and a maintainer will move the conversation to a private channel.

Please include: the affected file/section (spec text, schema, reference implementation), a reproduction or worked example, and the impact you foresee. You can expect an acknowledgment within 7 days.

In scope:

• Spec-level weaknesses: anything that makes a conforming implementation unsafe (e.g. a gap in the MUSCLE capability model, path-template escapes, YAML loading guidance).
• The reference implementations in this repo: reference/muscle-host/, reference/cli/, reference/fountain-adapter/, reference/continuity-guard/, scripts/.
• The published schemas (validation bypasses with security consequences).

Out of scope:

• Vulnerabilities in third-party hosts or plugins (report to their maintainers; if the spec let them be vulnerable, that part is in scope here).
• Genlock Studio the application (separate codebase; reports reach the same maintainers, but file them against the app).

The normative security requirements implementations must follow live in the specs themselves:

• skel-spec.md §10 — YAML safe loading, alias/size caps, external key-file integrity, path safety, NFC.
• muscle-spec.md §10 — consent-based enablement, argv-style invocation, payload/patch caps, filesystem boundaries, envelope privacy.

The latest MINOR release of the 2.x spec line and the reference implementations at main. Older tagged releases receive errata only for vulnerabilities that make conforming implementations unsafe.