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.
90
88%
Does it follow best practices?
Impact
Pending
No eval scenarios have been run
Advisory
Suggest reviewing before use
Quality
Discovery
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.
This is an excellent skill description that clearly defines its scope around the Linux Audit framework with specific tools, actions, and use cases. It includes an explicit activation clause with natural trigger terms that security professionals would use. The description is concise yet comprehensive, covering both capabilities and trigger conditions without unnecessary verbosity.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple specific concrete actions: detect intrusion attempts, unauthorized access, privilege escalation, suspicious activity, audit rule configuration, log querying, timeline reconstruction, and SIEM integration. Names specific tools (auditd, ausearch, aureport). | 3 / 3 |
Completeness | Clearly answers both 'what' (detect intrusions, configure audit rules, query logs, reconstruct timelines, integrate with SIEM) and 'when' with an explicit 'Activates for...' clause listing specific trigger scenarios like auditd analysis, ausearch queries, and aureport summaries. | 3 / 3 |
Trigger Term Quality | Excellent coverage of natural terms users would say: 'auditd', 'ausearch', 'aureport', 'Linux audit log', 'intrusion detection', 'privilege escalation', 'SIEM', 'host-based intrusion detection'. These are terms a security professional would naturally use. | 3 / 3 |
Distinctiveness Conflict Risk | Highly distinctive niche focused specifically on the Linux Audit framework (auditd/ausearch/aureport). Unlikely to conflict with general security skills or other log analysis skills due to the specific tooling and platform focus. | 3 / 3 |
Total | 12 / 12 Passed |
Implementation
77%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This is a strong, highly actionable skill with excellent executable examples and a well-sequenced workflow including proper validation checkpoints. Its main weakness is length—the comprehensive audit rules and extensive command examples make it token-heavy, and some content (Key Concepts table, SIEM forwarding) could be trimmed or moved to referenced files. The skill would benefit from splitting the detailed rules and query examples into separate reference documents.
Suggestions
Move the Key Concepts table to a referenced file or remove it entirely—Claude already knows what auditd, ausearch, and aureport are.
Extract the detailed audit rules block (Step 2) into a separate referenced file like `intrusion-rules.rules` and keep only 2-3 example rules inline to illustrate the pattern.
Either expand the SIEM forwarding section (Step 6) into a proper referenced guide or reduce it to a one-line pointer to external documentation.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The skill is generally well-structured but includes some unnecessary content. The Key Concepts table explains terms like 'auditd' and 'ausearch' that Claude already knows. The Prerequisites section over-explains basics. The SIEM forwarding section (Step 6) is thin and could be a reference link instead of inline content. However, the audit rules and command examples are dense and valuable. | 2 / 3 |
Actionability | Every step contains concrete, copy-paste-ready bash commands. The audit rules in Step 2 are fully deployable, ausearch and aureport commands in Steps 3-4 are executable with real flags and keys, and the timeline reconstruction in Step 5 provides a specific investigative methodology with actual command sequences. | 3 / 3 |
Workflow Clarity | The six-step workflow is clearly sequenced from verification through rule deployment, querying, reporting, timeline reconstruction, and SIEM integration. Validation checkpoints are explicit: Step 1 checks daemon status and backlog, the reload step confirms rule count, and the Verification section provides a comprehensive checklist including testing that rules trigger correctly and persist across reboot. | 3 / 3 |
Progressive Disclosure | The content is well-organized with clear sections and a logical flow, but it's a long monolithic document (~180 lines of substantive content). The extensive audit rules block and numerous ausearch/aureport examples could be split into referenced files (e.g., a rules template file, a query cookbook). The SIEM section is too thin to be useful inline but too present to ignore—it would be better as a reference to a dedicated guide. | 2 / 3 |
Total | 10 / 12 Passed |
Validation
90%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 10 / 11 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
frontmatter_unknown_keys | Unknown frontmatter key(s) found; consider removing or moving to metadata | Warning |
Total | 10 / 11 Passed | |
- Repository
- mukul975/Anthropic-Cybersecurity-Skills
- Commit
888bbe4
- Reviewed
Table of Contents
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