| name | detecting-rdp-brute-force-attacks |
| description | Detect RDP brute force attacks by analyzing Windows Security Event Logs for failed authentication patterns (Event ID 4625), successful logons after failures (Event ID 4624), NLA failures, and source IP frequency analysis. Use when detecting rdp brute force attacks by analyzing windows security event. |
| domain | cybersecurity |
| subdomain | threat-detection |
| tags | ["threat-detection","rdp","brute-force","windows-event-logs","blue-team","siem"] |
| version | 1.0 |
| author | oyi77 |
| license | Apache-2.0 |
| nist_csf | ["DE.CM-01","DE.AE-02","DE.AE-06","ID.RA-05"] |
Detecting RDP Brute Force Attacks
Overview
RDP brute force attacks target Windows Remote Desktop Protocol services by attempting rapid credential guessing against exposed RDP endpoints. Detection relies on analyzing Windows Security Event Logs for Event ID 4625 (failed logon with Logon Type 10 or 3) and correlating with Event ID 4624 (successful logon) to identify compromised accounts. This skill covers parsing EVTX files with python-evtx, identifying attack patterns through source IP frequency analysis, detecting NLA bypass attempts, and generating actionable detection reports.
When to Use
Trigger phrases:
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"detecting rdp brute force attacks"
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"Detect RDP brute force attacks by analyzing Windows Security Event Logs for fail"
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When investigating security incidents that require detecting rdp brute force attacks
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When building detection rules or threat hunting queries for this domain
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When SOC analysts need structured procedures for this analysis type
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When validating security monitoring coverage for related attack techniques
Prerequisites
- Python 3.9+ with
python-evtx, lxml libraries
- Windows Security EVTX log files (exported from Event Viewer or collected via WEF)
- Understanding of Windows authentication Event IDs (4624, 4625, 4776)
- Familiarity with RDP Logon Types (Type 3 for NLA, Type 10 for RemoteInteractive)
Steps
- Scope and authorize — confirm written authorization and define target boundaries
- Reconnaissance — enumerate targets, services, and potential attack surfaces
- Exploitation — attempt exploitation of identified vulnerabilities within scope
- Post-exploitation — document access level, lateral movement, and data exposure
- Report and remediate — compile findings with reproduction steps and fix recommendations
Step 1: Export Security Event Logs
Export Windows Security logs to EVTX format using Event Viewer or wevtutil:
wevtutil epl Security C:\logs\security.evtx
Step 2: Parse Failed Logon Events
Use python-evtx to parse Event ID 4625 entries, extracting source IP, target username, failure reason (Sub Status), and Logon Type fields.
Step 3: Analyze Attack Patterns
Identify brute force patterns by:
