Files
Anthropic-Cybersecurity-Skills/skills/analyzing-powershell-empire-artifacts/SKILL.md
T
Mahipal 2fb6a9faff Rewrite 548 skill descriptions to the activation rubric
Each rewritten description now states both what the skill does (concrete
capability, named tools/artifacts) and an explicit when-to-use trigger,
improving agent discovery/activation. Grounded in each skill's own body;
changes confined to the `description` field only (bodies and all other
frontmatter untouched). Produced by a gated audit->rewrite->recheck loop
(548 -> 0 flagged) with a sampled anti-invention check (0 ungrounded).

Schema: 817/817 pass. Framework-ID gate: 0 defects.
2026-08-02 09:32:13 -07:00

2.8 KiB

name, description, domain, subdomain, tags, version, author, license, d3fend_techniques, nist_ai_rmf, nist_csf, mitre_attack
name description domain subdomain tags version author license d3fend_techniques nist_ai_rmf nist_csf mitre_attack
analyzing-powershell-empire-artifacts Detect PowerShell Empire post-exploitation framework artifacts in Windows Script Block Logging (Event ID 4104) and Module Logging (Event ID 4103), including the default launcher string, Base64-encoded WebClient/FromBase64String payloads, known module invocations (Invoke-Mimikatz, Invoke-Kerberoast), and staging URL patterns. Use when hunting for or confirming Empire C2 activity in Windows event logs. cybersecurity threat-hunting
PowerShell-Empire
threat-hunting
Script-Block-Logging
base64
stager
C2
MITRE-ATT&CK
T1059.001
forensics
1.0 mahipal Apache-2.0
Executable Denylisting
Execution Isolation
File Metadata Consistency Validation
Content Format Conversion
File Content Analysis
GOVERN-1.1
MEASURE-2.7
MANAGE-3.1
DE.CM-01
DE.AE-02
DE.AE-07
ID.RA-05
T1059.001
T1071.001
T1003.001
T1558.003
T1027.010

Analyzing PowerShell Empire Artifacts

Overview

PowerShell Empire is a post-exploitation framework consisting of listeners, stagers, and agents. Its artifacts leave detectable traces in Windows event logs, particularly PowerShell Script Block Logging (Event ID 4104) and Module Logging (Event ID 4103). This skill analyzes event logs for Empire's default launcher string (powershell -noP -sta -w 1 -enc), Base64 encoded payloads containing System.Net.WebClient and FromBase64String, known module invocations (Invoke-Mimikatz, Invoke-Kerberoast, Invoke-TokenManipulation), and staging URL patterns.

When to Use

  • When investigating security incidents that require analyzing powershell empire artifacts
  • When building detection rules or threat hunting queries for this domain
  • When SOC analysts need structured procedures for this analysis type
  • When validating security monitoring coverage for related attack techniques

Prerequisites

  • Python 3.9+ with access to Windows Event Log or exported EVTX files
  • PowerShell Script Block Logging (Event ID 4104) enabled via Group Policy
  • Module Logging (Event ID 4103) enabled for comprehensive coverage

Key Detection Patterns

  1. Default launcherpowershell -noP -sta -w 1 -enc followed by Base64 blob
  2. Stager indicatorsSystem.Net.WebClient, DownloadData, DownloadString, FromBase64String
  3. Module signatures — Invoke-Mimikatz, Invoke-Kerberoast, Invoke-TokenManipulation, Invoke-PSInject, Invoke-DCOM
  4. User agent strings — default Empire user agents in HTTP listener configuration
  5. Staging URLs/login/process.php, /admin/get.php and similar default URI patterns

Output

JSON report with matched IOCs, decoded Base64 payloads, timeline of suspicious events, MITRE ATT&CK technique mappings, and severity scores.