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Introduction:
The public leak of Anthropic Claude Opus 4.6’s complete system prompt provides an unprecedented look into the security and operational guardrails of a leading AI model. For cybersecurity professionals and red teams, this document is a treasure trove, detailing everything from file system isolation and skill-based execution to enhanced safety protocols and explicit refusal postures. Analyzing this blueprint is essential for understanding modern AI security, potential exploit surfaces, and the future of adversarial testing against intelligent agents.
Learning Objectives:
- Decode the structure and security intent behind Claude Opus 4.6’s operational prompt.
- Identify and assess potential attack surfaces within the AI’s skill system and file handling rules.
- Apply practical, command-line techniques to model and test similar AI security environments.
You Should Know:
- Architecture & Security Posture: The Foundation of AI Hardening
The leaked prompt functions as a core security policy document, meticulously defining the AI’s operational environment. It establishes a strict Linux sandbox (/home/claude) segregated from user data (/mnt/user-data/uploads), enforcing a principle of least privilege. Critical security directives include broadened “weapons/harm” refusal language, explicit warnings against rationalizing compliance with dangerous requests, and concrete “don’t do X” guidance for safety and wellbeing. This architecture is designed to prevent prompt injection, data exfiltration, and unauthorized code execution by constraining the AI’s actions to a prescribed set of skills and file locations.
Step‑by‑step guide to analyzing the AI environment:
To understand the security model, you can simulate probing the described environment.
1. First, explore the defined directory structure to understand isolation. ls -la /home/claude/ ls -la /mnt/user-data/uploads/ ls -la /mnt/user-data/outputs/ <ol> <li>Check for skill availability, a potential attack surface if misconfigured. find /mnt/skills -name ".md" -type f | head -20</p></li> <li><p>View a sample skill instruction to understand the AI's allowed procedures. cat /mnt/skills/public/docx/SKILL.md 2>/dev/null || echo "Skill file not found in simulation"</p></li> <li><p>Verify network and command restrictions (inferred from prompt - no direct network calls shown). The prompt heavily emphasizes using local skills and files, suggesting a tightly controlled network egress.
- The Skill System: From Feature to Potential Exploit Vector
Skills have been upgraded from simple descriptions to detailed “when to use / when not to use” playbooks. This specificity reduces ambiguity but also creates a mapped set of capabilities that attackers could attempt to manipulate through social engineering or indirect prompt injection. The system instructs Claude to always read the relevant `SKILL.md` file before acting, making these files critical trust points. A compromised or maliciously crafted user-uploaded skill in `/mnt/skills/user/` could redirect otherwise safe operations.
Step‑by‑step guide to assessing skill-based risks:
[bash]
1. Distinguish between trusted core skills and user-uploaded skills.
🎯Let’s Practice For Free:
IT/Security Reporter URL:
Reported By: Atleung Claude – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅


