hunting-for-ntlm-relay-attacks
Detect NTLM relay attacks by analyzing Windows Event 4624 logon type 3 with NTLMSSP authentication, identifying IP-to-hostname mismatches, Responder traffic signatures, SMB signing status, and suspicious authentication patterns across the domain.
Best use case
hunting-for-ntlm-relay-attacks is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
Detect NTLM relay attacks by analyzing Windows Event 4624 logon type 3 with NTLMSSP authentication, identifying IP-to-hostname mismatches, Responder traffic signatures, SMB signing status, and suspicious authentication patterns across the domain.
Teams using hunting-for-ntlm-relay-attacks should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/hunting-for-ntlm-relay-attacks/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How hunting-for-ntlm-relay-attacks Compares
| Feature / Agent | hunting-for-ntlm-relay-attacks | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
Detect NTLM relay attacks by analyzing Windows Event 4624 logon type 3 with NTLMSSP authentication, identifying IP-to-hostname mismatches, Responder traffic signatures, SMB signing status, and suspicious authentication patterns across the domain.
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# Hunting for NTLM Relay Attacks ## Overview NTLM relay attacks intercept and forward NTLM authentication messages to gain unauthorized access to network resources. Attackers use tools like Responder for LLMNR/NBT-NS poisoning and ntlmrelayx for credential relay. This skill detects relay activity by querying Windows Security Event 4624 (successful logon) for type 3 network logons with NTLMSSP authentication, identifying mismatches between WorkstationName and source IpAddress, detecting rapid multi-host authentication from single accounts, and auditing SMB signing configuration across domain hosts. ## When to Use - When investigating security incidents that require hunting for ntlm relay attacks - 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 Windows Event Log access or exported logs - Windows Security audit logging enabled (Event ID 4624, 4625, 5145) - Network access for SMB signing status checks ## Key Detection Areas 1. **IP-hostname mismatch** — WorkstationName in Event 4624 does not resolve to the source IpAddress 2. **NTLMSSP authentication** — logon events using NTLM instead of Kerberos from domain-joined hosts 3. **Machine account relay** — computer accounts (ending in $) authenticating from unexpected IPs 4. **Rapid authentication** — single account authenticating to multiple hosts within seconds 5. **Named pipe access** — Event 5145 showing access to Spoolss, lsarpc, netlogon, samr pipes 6. **SMB signing disabled** — hosts not enforcing SMB signing, enabling relay attacks ## Output JSON report with suspected relay events, IP-hostname correlation anomalies, SMB signing audit results, and MITRE ATT&CK mapping to T1557.001.