analyzing-powershell-script-block-logging
Parse Windows PowerShell Script Block Logs (Event ID 4104) from EVTX files to detect obfuscated commands, encoded payloads, and living-off-the-land techniques. Uses python-evtx to extract and reconstruct multi-block scripts, applies entropy analysis and pattern matching for Base64-encoded commands, Invoke-Expression abuse, download cradles, and AMSI bypass attempts.
60
70%
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High
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tessl review fix ./skills/analyzing-powershell-script-block-logging/SKILL.mdSecurity
1 high severity finding. You should review these findings carefully before considering using this skill.
W007: Insecure credential handling detected in skill instructions.
What this means
The skill handles credentials insecurely by requiring the agent to include secret values verbatim in its generated output. This exposes credentials in the agent’s context and conversation history, creating a risk of data exfiltration.
Why it was flagged
The prompt requires reconstructing and reporting full PowerShell script blocks from event logs, which can include sensitive secrets (passwords, tokens, keys) and therefore would force the agent to handle/output secret values verbatim.
Low
Low-risk findings.
1 low severity finding. Worth noting, but not necessarily harmful.
W011: Third-party content exposure detected (indirect prompt injection risk).
What this means
The skill exposes the agent to untrusted, user-generated content from public third-party sources, creating a risk of indirect prompt injection. This includes browsing arbitrary URLs, reading social media posts or forum comments, and analyzing content from unknown websites.
Why it was flagged
The runtime path reads OUTSIDER-authored free text from the user-supplied EVTX file (`--evtx-file`), parses Event 4104 `ScriptBlockText`/`MessageNumber`/etc. as XML text, reconstructs it, and then feeds the reconstructed `script_text` into the LLM context (via any downstream LLM step); since the EVTX contents are not authored by the operating user, this is outsider-provided log content.
- Repository
- mukul975/Anthropic-Cybersecurity-Skills
- Commit
9429fe9
- Audited
- Security analysis
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