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html-smuggling-lure

HTML smuggling payloads for initial access — embed base64-encoded binaries inside an HTML attachment that reconstructs and auto-downloads the file client-side via JavaScript Blob, bypassing email gateway and proxy file-type inspection.

56

Quality

66%

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SecuritybySnyk

Critical

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tessl review fix ./packages/decepticon/decepticon/skills/standard/phisher/html-smuggling-lure/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

65%

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

The content is highly actionable with executable code and a useful decision gate, but it loses points for a padded intro, a missing pre-send validation checkpoint for batch delivery, and a lack of file-splitting where detail could be externalized. It is well-structured but not optimally progressive.

Suggestions

Trim the introductory mechanism explanation and the historical campaign reference; assume reader familiarity to improve token efficiency.

Add an explicit validation checkpoint — test delivery against a single target before mass campaign send — to satisfy batch-operation verification and raise workflow clarity.

Move detailed obfuscation techniques and detection signatures into separate reference files (e.g., OBFUSCATION.md, DETECTION.md) with clearly signaled links to improve progressive disclosure.

DimensionReasoningScore

Conciseness

The body is mostly lean and action-oriented (executable commands, full scripts, tables, decision gate), but the opening paragraph explaining the smuggling mechanism plus the "Nobelium (SolarWinds), Qakbot, and IcedID campaigns..." reference are unnecessary orientation that assumes the reader lacks familiarity, matching level 2; not level 3 because of that padding, not level 1 because the bulk is efficient and copy-paste ready.

2 / 3

Actionability

Provides fully executable, copy-paste-ready material — base64 encoding and GoPhish curl commands, a complete Python generator script, a complete HTML template, and complete obfuscation functions (XOR, chunked reassembly, external fetch) — matching the level-3 anchor; not level 2 because there is no pseudocode or missing key details.

3 / 3

Workflow Clarity

A clear sequence (encode → generate → deliver) exists with a strong IF/ELIF Decision Gate and an Error Handling section, but a batch/campaign-delivery operation lacks an explicit pre-send validation/test step (single-target verification before mass delivery), so per the guidelines workflow clarity is capped at 2; not level 1 because sequencing and error-recovery paths are present.

2 / 3

Progressive Disclosure

Sections are well organized (Prerequisites, Quick Reference, numbered sections, OPSEC, Detection, Error Handling, Decision Gate) with no nested references, but no bundle files exist and ~290 lines of inline content (detailed obfuscation techniques, detection signatures) that could be externalized is kept inline, matching level 2; not level 3 because content is not split across one-level-deep reference files, not level 1 because it is not a monolithic wall of text with deep nesting.

2 / 3

Total

9

/

12

Passed

Description

67%

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

The description is specific and distinctive, but relies on technical jargon for triggers and omits an explicit "Use when..." clause, capping completeness and trigger quality at the middle level. Voice is appropriately third person with no first/second-person penalty.

Suggestions

Add an explicit "Use when..." clause (or equivalent trigger guidance) so completeness is not capped at 2.

Include natural user-facing trigger terms such as "phishing attachment" or "initial-access payload" alongside the technical jargon to raise trigger-term quality.

DimensionReasoningScore

Specificity

Quotes multiple concrete actions — "embed base64-encoded binaries inside an HTML attachment", "reconstructs and auto-downloads the file client-side via JavaScript Blob", "bypassing email gateway and proxy file-type inspection" — matching the level-3 anchor of several specific concrete actions; not level 2 because it lists more than a domain plus partial actions.

3 / 3

Completeness

Clearly answers "what" (smuggling payloads for initial access with a described mechanism) but the description field lacks an explicit "Use when..." clause; per the judging guidelines a missing explicit trigger clause caps completeness at 2, and it is not level 1 because the what-side is strong rather than weak.

2 / 3

Trigger Term Quality

Relevant keywords appear ("HTML smuggling", "base64", "email attachment", "initial access") but the phrasing leans on technical jargon ("JavaScript Blob", "proxy file-type inspection") rather than natural user wording, so it matches level 2 (some relevant keywords, missing common variations); not level 3 because natural variations like "phishing attachment" or "initial-access payload" are absent.

2 / 3

Distinctiveness Conflict Risk

Occupies a clear niche (HTML smuggling for initial access) with distinctive triggers unlikely to overlap with unrelated skills, matching the level-3 anchor; not level 2 because the specificity makes mis-triggering unlikely.

3 / 3

Total

10

/

12

Passed

Validation

87%

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

Validation14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

metadata_field

'metadata' should map string keys to string values

Warning

Total

14

/

16

Passed

Repository
PurpleAILAB/Decepticon
Reviewed

Table of Contents

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