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mfa-bypass

2FA / OTP logic flaws — response & status tampering, brute force, OTP reuse, backup-code abuse, race conditions, missing-2FA on flows, remember-me bypass, password-reset skips 2FA.

63

Quality

75%

Does it follow best practices?

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SecuritybySnyk

Critical

Do not install without reviewing

Fix and improve this skill with Tessl

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

Quality

Content

75%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.

The content is an efficient, actionable playbook with executable probes, a flaw matrix, and a validation decision gate. The main gaps are the prose-only race-condition PoC and the absence of any reference split or verify-retry loop.

Suggestions

Replace the 3.4 prose description with an executable Turbo Intruder / single-packet script (or a concrete command) so every PoC is runnable.

Add an explicit verify→fix→retry loop around the exploitation workflow (e.g. re-confirm the bypass after a session/token rotation) to strengthen feedback beyond the decision gate.

Trim the intro paragraph so it scopes the playbook without re-listing bypass classes already in the matrix.

DimensionReasoningScore

Conciseness

The body is lean and assumes Claude's competence (no primers on what 2FA or a JWT is), but the intro paragraph lightly previews bypass classes already enumerated in the matrix, a minor redundancy that keeps it just below fully lean.

4 / 5

Actionability

Detection and PoC sections give mostly copy-paste-ready curl/bash (inventory loop, rate-limit probe, brute-force loop, response-flip, direct-endpoint access); the single gap is 3.4, which describes the Turbo Intruder single-packet attack in prose instead of executable code.

4 / 5

Workflow Clarity

A clear Detection → Flaw matrix → Exploit → Chains → Tools → OPSEC → Decision Gate sequence with an explicit validation checklist and confirmation checks; falls short of 5 because a validate→fix→retry feedback loop for the exploitation itself is thinner than the decision-gate checklist.

4 / 5

Progressive Disclosure

No bundle files exist and the skill is a single self-contained document, but it is well-organized into numbered sections plus a table and decision gate with clear header navigation; the all-inline ~125-line body keeps it at good structure rather than a clean overview-with-references split.

4 / 5

Total

16

/

20

Passed

Description

75%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.

The description is specific and well-scoped to a distinct MFA-bypass niche with strong trigger keywords, but it lacks any explicit 'Use when...' guidance, which limits completeness. Adding a trigger clause would lift the weakest dimension.

Suggestions

Append an explicit 'Use when ...' clause naming natural user phrases (e.g. 'Use when testing 2FA/MFA, OTP, TOTP, SMS-code, or step-up authentication bypass').

Add the missing synonyms MFA, TOTP, SMS, and authenticator to broaden trigger-term coverage.

Keep the concrete bypass-class list — it is the description's strongest asset.

DimensionReasoningScore

Specificity

Lists many specific concrete bypass classes — 'response & status tampering, brute force, OTP reuse, backup-code abuse, race conditions, missing-2FA on flows, remember-me bypass, password-reset skips 2FA' — giving comprehensive coverage of the MFA-bypass domain rather than generic actions.

5 / 5

Completeness

The 'what' is clear and specific, but there is no 'Use when...' clause or equivalent explicit trigger guidance in the description, which per the rubric caps completeness at 3.

3 / 5

Trigger Term Quality

Good natural keyword coverage (2FA, OTP, brute force, remember-me, backup-code, password-reset, race conditions) but missing common synonyms a user might say such as MFA, TOTP, SMS, or authenticator in the description itself.

4 / 5

Distinctiveness Conflict Risk

A clearly delineated niche (2FA/OTP logic flaws for account takeover) with highly specific trigger classes, making confusion with unrelated skills unlikely.

5 / 5

Total

17

/

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

metadata_version

'metadata.version' is missing

Warning

Total

15

/

16

Passed

Repository
PurpleAILAB/Decepticon
Reviewed

Table of Contents

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