From reverse-engineering
Understand anti-reversing, obfuscation, and protection techniques encountered during software analysis. Use this skill when analyzing malware evasion techniques, when implementing anti-debugging protections for CTF challenges, when reverse engineering packed binaries, or when building security research tools that need to detect virtualized environments.
How this skill is triggered — by the user, by Claude, or both
Slash command
/reverse-engineering:anti-reversing-techniquesThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
> **AUTHORIZED USE ONLY**: This skill contains dual-use security techniques. Before proceeding with any bypass or analysis:
AUTHORIZED USE ONLY: This skill contains dual-use security techniques. Before proceeding with any bypass or analysis:
- Verify authorization: Confirm you have explicit written permission from the software owner, or are operating within a legitimate security context (CTF, authorized pentest, malware analysis, security research)
- Document scope: Ensure your activities fall within the defined scope of your authorization
- Legal compliance: Understand that unauthorized bypassing of software protection may violate laws (CFAA, DMCA anti-circumvention, etc.)
Legitimate use cases: Malware analysis, authorized penetration testing, CTF competitions, academic security research, analyzing software you own/have rights to
Understanding protection mechanisms encountered during authorized software analysis, security research, and malware analysis. This knowledge helps analysts bypass protections to complete legitimate analysis tasks.
For advanced techniques, see references/advanced-techniques.md
What you provide:
What this skill produces:
Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.
Detection technique works on x86 but not ARM
RDTSC and CPUID are x86-only. On ARM, use MRS x0, PMCCNTR_EL0 (requires kernel PMU access) or clock_gettime(CLOCK_MONOTONIC). PEB/TEB do not exist on ARM — replace with /proc/self/status (Linux) or task_info (macOS). Rebuild detection logic with platform-specific APIs.
False positive on legitimate debugger or analysis tool
Timing checks fire when Process Monitor or AV hooks inflate syscall latency. Calibrate the threshold at startup: measure the guarded path 3 times and use mean + 3*stddev. For ptrace checks, verify the TracerPid comm name via /proc/<pid>/comm before exiting — it may be an unrelated monitoring tool, not a debugger.
Bypass patch causes crash instead of continuing execution
Before NOPing a conditional jump, trace the "detected" branch fully. If it initializes or frees heap state needed later, patching the jump skips that setup and corrupts state. Instead, patch the comparison operand to the expected "clean" value, or use x64dbg's "Set condition to always false" on the breakpoint rather than modifying bytes.
binary-analysis-patterns — static and dynamic analysis workflows for ELF/PE/Mach-Omemory-forensics — process memory acquisition, artifact extraction, and live analysisprotocol-reverse-engineering — decoding custom binary protocols and encrypted network trafficnpx claudepluginhub yo-steven/agents-exploration-20260523 --plugin reverse-engineeringProvides CDSS development patterns for drug interaction checking, dose validation, clinical scoring (NEWS2, qSOFA), and alert classification integrated into EMR workflows.