analyzing-linux-audit-logs-for-intrusion

Uses the Linux Audit framework (auditd) with ausearch and aureport utilities to detect intrusion attempts, unauthorized access, privilege escalation, and suspicious system activity. Covers audit rule configuration, log querying, timeline reconstruction, and integration with SIEM platforms. Activates for requests involving auditd analysis, Linux audit log investigation, ausearch queries, aureport summaries, or host-based intrusion detection on Linux.

Quality

—

Does it follow best practices?

Impact

—

No eval scenarios have been run

Securityby

Advisory

Suggest reviewing before use

Quality

Content

92%

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 and well-sequenced with validation checkpoints, but it underuses progressive disclosure: the provided api-reference.md bundle is never referenced from the body, and content that belongs in a separate file is inlined.

Suggestions

Link the existing references/api-reference.md from the body (e.g., a 'See api-reference.md for full ausearch/aureport flag reference' line) so the bundle is discoverable.

Move the detailed ausearch/aureport command-flag listings out of the SKILL.md body into references/api-reference.md, keeping the body as a concise workflow overview.

Add a brief inline validate-fix-retry note after rule deployment (e.g., reload, verify count, fix and reload if mismatched) to make the feedback loop explicit rather than relying on the end checklist.

Dimension	Reasoning	Score
Conciseness	The body is lean and command-driven with minimal prose, avoiding padding with concepts Claude already knows; the Key Concepts table defines tools for precise command selection rather than explaining generic background.	3 / 3
Actionability	It provides fully executable, copy-paste-ready bash commands throughout (auditctl rules, ausearch/aureport queries with concrete flags and time ranges), matching the anchor for specific executable examples.	3 / 3
Workflow Clarity	A clear six-step sequence is present with inline validation checkpoints (backlog check, rule-count confirmation) plus a dedicated Verification checklist, so validation steps are not missing for the batch rule-deployment operations.	3 / 3
Progressive Disclosure	Although a references/api-reference.md bundle exists, the body never signals or links it, and detailed ausearch/aureport flag references that could live in that file are inlined as a large monolithic block.	2 / 3
	Total	11 / 12 Passed

Description

100%

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, complete, and distinct: it enumerates concrete capabilities and provides an explicit trigger clause covering natural terms users would say. It uses proper third-person voice and avoids vague fluff or over-claims.

Dimension	Reasoning	Score
Specificity	The description lists multiple concrete actions ('detect intrusion attempts, unauthorized access, privilege escalation', 'audit rule configuration, log querying, timeline reconstruction, and integration with SIEM platforms'), matching the anchor for listing multiple specific concrete actions.	3 / 3
Completeness	It clearly answers both what the skill does and when to use it via the explicit 'Activates for requests involving...' trigger clause, matching the anchor for clearly answering both what AND when.	3 / 3
Trigger Term Quality	It gives good coverage of natural terms a user would say ('auditd analysis, Linux audit log investigation, ausearch queries, aureport summaries, or host-based intrusion detection on Linux'), aligning with the score-3 anchor rather than the partial coverage of score 2.	3 / 3
Distinctiveness Conflict Risk	It targets a clear niche (Linux host-based audit log intrusion detection) with distinct triggers and even distinguishes itself from network-level IDS, making it unlikely to conflict with other skills.	3 / 3
	Total	12 / 12 Passed

Validation

93%

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 — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	15 / 16 Passed

Repository: mukul975/Anthropic-Cybersecurity-Skills
Commit: 673da1f

Reviewed: 13 days ago

Table of Contents

Discovery Implementation Validation

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