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hunt-race-condition

Hunting skill for race condition vulnerabilities. Built from 12 public bug bounty reports including modern HTTP/2 single-packet attack cases (James Kettle DEF CON 2023 "Smashing the State Machine"; RyotaK / Flatt Security 10,000-request first-sequence-sync expansion 2024). Covers coupon double-redemption, gift-card double-spend, MFA-OTP-validate race, account-create race, faucet/crypto token double-mint, email-activation race, vote/upvote inflation, password-reset token race, rate-limit bypass via concurrent requests. Use when hunting race conditions, TOCTOU bugs, MFA-bypass-via-timing.

68

Quality

83%

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SecuritybySnyk

Critical

Do not install without reviewing

SKILL.md
Quality
Evals
Security

Quality

Content

77%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 content with executable tooling and a well-validated hunting workflow, but it is a verbose monolith that repeats the single-packet technique across sections and inlines deep-reference and citation material that would benefit from separate bundle files.

Suggestions

Move the HTTP/2 Single-Packet Deep Reference and the Disclosed Report Citations into separate files under references/ and keep SKILL.md as a concise overview that links one level deep, which would improve both conciseness and progressive_disclosure.

De-duplicate the single-packet explanation: keep one canonical description (the Deep Reference) and have the earlier Firing-a-race section briefly point to it instead of re-explaining the technique.

Tighten the Real Impact Examples — three full prose scenarios restate the cited cases; condensing to one-liners that reference the citation numbers would cut tokens without losing signal.

DimensionReasoningScore

Conciseness

Mostly efficient specialist content, but the ~485-line body explains the HTTP/2 single-packet attack at three different depths (Firing a race, the citation list, and the Deep Reference) and the three verbose Real Impact scenarios largely restate the cited cases, so it could be tightened.

3 / 5

Actionability

Provides copy-paste-ready, executable artifacts throughout — a complete line-by-line Turbo Intruder BURP2 template, curl/asyncio/grep snippets, tcpdump+Wireshark validation commands, and a concrete 7-step race-window estimation methodology covering the common cases.

5 / 5

Workflow Clarity

A 10-step numbered hunting methodology with explicit validation checkpoints ("Analyze responses", "Verify the effect", reproducibility over 5 attempts) plus a Gate 0 validation section that gates reporting on demonstrated harm and reproducibility — clear sequence with feedback loops and a checklist.

5 / 5

Progressive Disclosure

Good in-file section headers give structure, but with no bundle files present the whole skill is a monolith: the Deep Reference and the 9 backfilled citations clearly belong in separate reference files, so content that should be split is inlined.

3 / 5

Total

16

/

20

Passed

Description

88%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 that comprehensively enumerates race-condition subclasses and pairs a clear what with an explicit Use-when clause. Minor overlap risk with adjacent hunting skills and slightly jargon-heavy trigger phrasing keep it just short of perfect.

DimensionReasoningScore

Specificity

Lists multiple specific concrete race subclasses — "coupon double-redemption, gift-card double-spend, MFA-OTP-validate race, account-create race, faucet/crypto token double-mint, email-activation race, vote/upvote inflation, password-reset token race, rate-limit bypass" — giving comprehensive coverage of the domain.

5 / 5

Completeness

Explicitly answers both what (a hunting skill covering the enumerated race subclasses) and when ("Use when hunting race conditions, TOCTOU bugs, MFA-bypass-via-timing") with concrete trigger phrases.

5 / 5

Trigger Term Quality

Includes natural phrases a user would say ("race conditions", "TOCTOU bugs", "hunting race conditions"), but "MFA-bypass-via-timing" and the cited researcher names are more jargon than natural trigger language, leaving a few common synonyms (e.g. "concurrency bugs") uncovered.

4 / 5

Distinctiveness Conflict Risk

The race-condition niche is clear and mostly distinct, but the "MFA-OTP-validate race" / "MFA-bypass-via-timing" triggers create minor overlap risk with sibling skills like hunt-mfa-bypass and hunt-business-logic.

4 / 5

Total

18

/

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.

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

15

/

16

Passed

Repository
elementalsouls/Claude-BugHunter
Reviewed

Table of Contents

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