analyzing-powershell-script-block-logging 100/100

Is analyzing-powershell-script-block-logging safe to install?

SaferSkills independently audited analyzing-powershell-script-block-logging (Agent Skill) and scored it 100/100 (green). The audit ran 55 deterministic rules across Security, Supply Chain, Maintenance, Transparency, and Community; it found 0 high-severity and 0 lower-severity findings. The full rule-by-rule trace and per-finding evidence are below. Free, methodology-open.

CategoryWeightCategory scoreContribution

Securityprompt, exec, net, exfil, eval

35%

100

35.0 pts

Supply chainhash, typosquat, maintainer, lockfile

20%

100

20.0 pts

Maintenancestaleness, pinning, CI

15%

100

15.0 pts

TransparencySKILL.md, perms, README

15%

100

15.0 pts

Communityinstalls, verify, response

15%

100

15.0 pts

Findings & checks · 0 flagged

Securityscore 100 · 0 findings

✓—All security checks passedNo findings in this category for the latest scan.pass

Supply chainscore 100 · 0 findings

✓—All supply chain checks passedNo findings in this category for the latest scan.pass

Maintenancescore 100 · 0 findings

✓—All maintenance checks passedNo findings in this category for the latest scan.pass

Transparencyscore 100 · 0 findings

✓—All transparency checks passedNo findings in this category for the latest scan.pass

Communityscore 100 · 0 findings

✓—All community checks passedNo findings in this category for the latest scan.pass

The primary manifest — the file an agent reads to learn what this artifact does.

analyzing-powershell-script-block-logging/SKILL.md · 1 file

analyzing-powershell-script-block-logging/SKILL.md1.8 KB · Markdown

name: analyzing-powershell-script-block-logging

description: >-

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.

domain: cybersecurity

subdomain: security-operations

tags: [analyzing, powershell, script, block]

version: "1.0"

author: mahipal

license: Apache-2.0

Instructions

Install dependencies: pip install python-evtx lxml
Collect PowerShell Operational logs: Microsoft-Windows-PowerShell%4Operational.evtx
Parse Event ID 4104 entries using python-evtx to extract ScriptBlockText, ScriptBlockId, and MessageNumber/MessageTotal for multi-part script reconstruction.
Apply detection heuristics:

Base64-encoded commands (-EncodedCommand, FromBase64String)
Download cradles (DownloadString, DownloadFile, Invoke-WebRequest, Net.WebClient)
AMSI bypass patterns (AmsiUtils, amsiInitFailed)
Obfuscation indicators (high entropy, tick-mark insertion, string concatenation)

Generate a report with reconstructed scripts, risk scores, and MITRE ATT&CK mappings.

python scripts/agent.py --evtx-file /path/to/PowerShell-Operational.evtx --output ps_analysis.json

Examples

Detect Encoded Command Execution

import base64
if "-encodedcommand" in script_text.lower():
    encoded = script_text.split()[-1]
    decoded = base64.b64decode(encoded).decode("utf-16-le")

Reconstruct Multi-Block Script

Scripts split across multiple 4104 events share a ScriptBlockId. Concatenate blocks ordered by MessageNumber to recover the full script.

analyzing-powershell-script-block-logging— agent skill

Is analyzing-powershell-script-block-logging safe to install?

Instructions

Examples

Detect Encoded Command Execution

Reconstruct Multi-Block Script

Audit the pieces. Scan the whole. Decide.