offensive-shellcode

Shellcode development reference for offensive security engagements. Use when writing custom x86/x64 shellcode, implementing position-independent code (PIC), building shellcode loaders, evading AV/EDR detection, or converting PE files to shellcode. Covers null byte avoidance, API hashing, encoder/decoder patterns, staged vs stageless payloads, Windows PEB traversal, and cross-platform shellcode techniques.

Quality

82%

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Securityby

Critical

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Quality

Content

72%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.

Highly actionable and well-structured offensive-shellcode reference with executable code, but it is a long monolithic single-file body and its destructive-operation workflows lack explicit validation checkpoints, which caps workflow clarity.

Suggestions

Add explicit validation/verification checkpoints to the Shellcode Development Workflow (e.g., assemble-and-test after each phase, a validate→fix→retry loop before delivery) to lift workflow clarity above the cap.

Move the full x64 reverse-shell code listing and the tool/reference tables into separate files under references/ (with short inline pointers from SKILL.md) to improve progressive disclosure and reduce token load.

Trim or offload the inline WinDbg helper block and lengthy tool tables to keep the overview body lean while retaining actionability.

Dimension	Reasoning	Score
Conciseness	Dense and assumes Claude's competence with no padding about what shellcode/PE/AV is, but the full ~250-line inline reverse-shell listing and reference tables are somewhat long and could be trimmed or offloaded.	4 / 5
Actionability	Provides copy-paste-ready executable guidance: a working RW→RX C snippet, fully commented PEB-walk assembly, a complete Python/Keystone reverse shell, and named external tools with links covering the common cases.	5 / 5
Workflow Clarity	A clear 6-step development workflow and sequenced loader phases (Allocate→Write→Execute) are present, but risky offensive operations lack explicit validation checkpoints or validate→fix→retry feedback loops, capping this dimension at 3 per the rubric.	3 / 5
Progressive Disclosure	Section structure is clear with well-organized headers and one-level-deep external links, but no bundle files exist and ~470 lines of content (full reverse-shell code, tool/API reference tables) that would belong in separate reference files are inlined.	3 / 5
	Total	15 / 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 strong, specific description with concrete actions and explicit 'Use when...' trigger guidance covering both what the skill does and when to invoke it. Trigger term quality is slightly below the top anchor but otherwise excellent.

Dimension	Reasoning	Score
Specificity	Lists multiple specific concrete actions ('writing custom x86/x64 shellcode', 'implementing position-independent code (PIC)', 'building shellcode loaders', 'evading AV/EDR detection', 'converting PE files to shellcode') plus comprehensive topic coverage, matching the comprehensive-coverage anchor.	5 / 5
Completeness	Explicitly answers both what ('Shellcode development reference... Covers null byte avoidance, API hashing...') and when ('Use when writing custom x86/x64 shellcode...'), with concrete trigger phrases.	5 / 5
Trigger Term Quality	Includes natural trigger phrases a user would actually say ('writing custom x86/x64 shellcode', 'building shellcode loaders', 'evading AV/EDR detection', 'converting PE files to shellcode') with good synonym coverage, though not quite the file-extension-level breadth of the top anchor.	4 / 5
Distinctiveness Conflict Risk	Occupies a clear offensive-shellcode niche with distinct triggers (PEB traversal, PE-to-shellcode, AV/EDR evasion) and minimal overlap risk with other skills.	5 / 5
	Total	19 / 20 Passed

Validation

100%

Warnings & errors only

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

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: SnailSploit/Claude-Red
Path: Skills/infrastructure/offensive-shellcode/SKILL.md
Commit: 24d7968

Reviewed: ~5 hours ago

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