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competition-kernel-container-escape

Internal downstream skill for ctf-sandbox-orchestrator. CTF-sandbox workflow for kernel attack surface, namespace and cgroup boundaries, container isolation assumptions, syscall paths, and escape primitive verification. Use when the user asks to analyze container-to-host escape paths, kernel exploit prerequisites, namespace crossover, capability misuse, or prove whether an exploit primitive crosses the sandbox boundary. Use only after `$ctf-sandbox-orchestrator` has already established sandbox assumptions and routed here.

68

Quality

81%

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SecuritybySnyk

Critical

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SKILL.md
Quality
Evals
Security

Quality

Content

71%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

Well-organized, lean security-analysis skill with a clear workflow and a properly signaled single reference. The main gap is actionability: it tells Claude what to observe but not which concrete commands or tools to use.

Suggestions

Add a short list of concrete commands/tools for the isolation mapping step (e.g. capsh --print, nsenter, cat /proc/self/status, findmnt, seccomp-tools dump) to lift actionability.

Merge the Quick Start and Workflow step 1 ('Map isolation') to remove redundancy and tighten conciseness.

Include one short before/after evidence-capture example (e.g. expected namespace/capability diff) to make the boundary-crossing proof step more executable.

DimensionReasoningScore

Conciseness

Lean checklist-style body that assumes Claude's competence and avoids explaining known concepts; the Quick Start and Workflow sections overlap slightly, which could be tightened.

4 / 5

Actionability

Gives concrete targets ('Record namespace map, cgroup mode, capabilities, seccomp profile...', 'Capture before and after identity, namespace, mount...') but no specific commands or tools (e.g. capsh, nsenter, /proc paths, seccomp-tools) to execute them.

3 / 5

Workflow Clarity

A clear three-stage sequence (Map -> Prove -> Reduce) with verification checkpoints such as 'Reproduce one minimal primitive-to-boundary-crossing chain' and 'Distinguish crash-only behavior from stable capability gain'.

4 / 5

Progressive Disclosure

Overview body with a single, clearly signaled one-level-deep reference ('Load references/kernel-container-escape.md for isolation checklist, primitive checklist, and parity guidance') that exists in the bundle.

5 / 5

Total

16

/

20

Passed

Description

92%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A tightly scoped, well-structured description that names concrete actions, gives explicit trigger phrases, and guards its downstream boundary. Minor room to add a few more user-natural synonyms for the trigger terms.

DimensionReasoningScore

Specificity

Lists multiple concrete actions — 'analyze container-to-host escape paths, kernel exploit prerequisites, namespace crossover, capability misuse, or prove whether an exploit primitive crosses the sandbox boundary' — giving comprehensive coverage of the niche.

5 / 5

Completeness

Explicitly answers what ('CTF-sandbox workflow for kernel attack surface, namespace and cgroup boundaries...') and when ('Use when the user asks to analyze...') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Natural niche phrases like 'container-to-host escape paths', 'namespace crossover', 'capability misuse', and 'exploit primitive' are present; a few common synonyms (e.g. 'container breakout', 'privilege escalation') are missing.

4 / 5

Distinctiveness Conflict Risk

A clearly bounded niche with an explicit routing guard ('Use only after $ctf-sandbox-orchestrator has already established sandbox assumptions and routed here'), minimizing conflict with sibling skills.

5 / 5

Total

19

/

20

Passed

Validation

100%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
zhaoxuya520/reverse-skill
Reviewed

Table of Contents

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