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proxy-misconfig

Reverse proxy misconfigurations — nginx alias traversal, Apache mod_rewrite SSRF, Spring Boot Actuator exposure, Tomcat manager, IIS short-name disclosure.

Quality

80%

Does it follow best practices?

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SecuritybySnyk

Critical

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Fix and improve this skill with Tessl

tessl review fix ./packages/decepticon/decepticon/skills/standard/exploit/web/proxy-misconfig/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

83%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.

An exceptionally lean and actionable reference catalog: copy-paste commands, concrete indicators, and a useful severity/defender split. The main weakness is workflow clarity — destructive sequences like the Tomcat WAR deploy lack validation checkpoints, and there is no top-level flow for selecting the right technique for a fingerprinted target.

Suggestions

Add validation steps to destructive sequences, e.g. after the Tomcat WAR deploy check the manager response and hit the deployed path only after confirming deploy succeeded.

Add a short selection flow at the top: fingerprint the server/proxy in front of the target (nginx vs Apache vs IIS vs Tomcat vs Spring) and jump to the matching numbered section.

Move external cross-references (ssrf.md, smuggling.md) into a references/ bundle directory within the skill so the links are verifiable and one level deep.

DimensionReasoningScore

Conciseness

The body is almost entirely lean, load-bearing code blocks with terse, high-value comments ('# trailing slash CRITICAL', '# 400 if exists, 404 if not — leaks first chars'). No explanations of concepts Claude already knows and no padding — every token earns its place, matching anchor 5.

5 / 5

Actionability

Copy-paste-ready curl, msfvenom, and wscat commands with concrete endpoints, an explicit default-credential list, exact response-code differentiators, and a working PoC-to-secret-extraction pipeline (heapdump → strings → grep). Fully executable and covers the common cases — anchor 5, not 4, since there are no meaningful gaps.

5 / 5

Workflow Clarity

Each technique has an implicit probe→confirm→exploit micro-sequence (e.g., Tomcat list → default creds → deploy WAR → trigger), but there are no explicit validation checkpoints for the destructive operations (WAR deploy → RCE has no 'verify deploy succeeded' step) and no overall workflow for choosing which technique applies to a given target. Per the guideline capping destructive-operation workflows without validation at 3, this lands at anchor 3 rather than 4.

3 / 5

Progressive Disclosure

Well-organized numbered sections with clearly signaled, one-level-deep delegation ('See skills/exploit/web/smuggling.md') and sensible split-out of severity and defender guidance. It does not reach anchor 5 because no bundle files exist and the cross-references point to paths outside the skill that cannot be verified, but references are clearly signaled and structure is good — anchor 4.

4 / 5

Total

17

/

20

Passed

Description

70%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 specific, well-targeted description with strong trigger terms and minimal conflict risk, hampered by the complete absence of a 'Use when...' trigger clause and minor coverage gaps versus the body's actual scope. Adding an explicit usage clause and one or two missing technique families would lift it substantially.

Suggestions

Append an explicit trigger clause, e.g. 'Use when testing reverse proxies, API gateways, or app servers (nginx, Apache, Tomcat, IIS, Spring Boot) for misconfigurations during a pentest.'

Mention the remaining techniques the body covers — X-Forwarded-For/header trust abuse, WebSocket Origin bypass, merge_slashes traversal — so the description's coverage matches the content.

Include a few natural synonyms users say ('path traversal', 'default credentials', 'management interface') to round out trigger terms.

DimensionReasoningScore

Specificity

Enumerates five concrete, named misconfiguration classes ('nginx alias traversal', 'Apache mod_rewrite SSRF', 'Spring Boot Actuator exposure', 'Tomcat manager', 'IIS short-name disclosure'), but frames them as topics without action verbs and omits classes the body covers (X-Forwarded-For trust, WebSocket origin bypass, merge_slashes). This matches anchor 4 — several specific items with minor coverage gaps — rather than 5 (comprehensive) or 3 (only 1-2 concrete actions).

4 / 5

Completeness

The 'what' is clear — a catalog of reverse proxy misconfiguration classes — but there is no 'Use when...' clause or equivalent explicit trigger guidance anywhere in the description, which caps completeness at 3 per the judging guidelines. This matches anchor 3 exactly and cannot reach anchor 4, which requires both 'what' and 'when'.

3 / 5

Trigger Term Quality

Contains natural terms users would say when they need this skill ('reverse proxy', 'nginx', 'Apache', 'Tomcat', 'actuator', 'SSRF', 'alias', 'IIS'), giving good keyword coverage. It falls short of anchor 5 because common variations like 'path traversal', 'X-Forwarded-For', 'default credentials', and 'management interface' are absent, but it is well above anchor 3's 'some relevant keywords'.

4 / 5

Distinctiveness Conflict Risk

A clear niche (reverse proxy / app-server misconfigurations) with highly distinct triggers like 'nginx alias traversal' and 'Spring Boot Actuator' that no sibling skill would plausibly claim. Minimal conflict risk — matches anchor 5.

5 / 5

Total

16

/

20

Passed

Validation

93%

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

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

Total

15

/

16

Passed

Repository

PurpleAILAB/Decepticon

Path

packages/decepticon/decepticon/skills/standard/exploit/web/proxy-misconfig/SKILL.md

Reviewed

Table of Contents

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