Event IDs, Password Attack Signatures, and Risk Documentation

4.4.DSkill

Expanding the Event ID Vocabulary

You already know 4624 and 4625 from 2.2.3. Four more Event IDs round out what you need for real log analysis:

📋 Event ID Reference — click each one
Successful logonROUTINE
A logon succeeded. Normal on its own — but unusual timing, location, or device makes it worth a second look.
⚠️Event 1102 deserves special treatment. Unlike every other event on this list, there's almost no innocent explanation for it appearing unexpectedly. If you see it in an investigation, that's the finding — not one clue among several.
4.4.D.3–5Concept

Reading Password Attack Signatures in Logs

Password spraying and credential stuffing can look superficially similar — both involve failed logins in a short window — but their actual log patterns are distinct once you know what to look for.

🔀 Spraying vs. Stuffing — click to compare
09:14:01 FAILED user: alice pw: Summer2026! 09:14:02 FAILED user: bmartin pw: Summer2026! 09:14:02 FAILED user: jchen pw: Summer2026! 09:14:03 FAILED user: rpatel pw: Summer2026!
Many different users, same password, same IP, seconds apart — one guess per account, betting that at least one user chose that exact password.
🔑Offline password attacks are the exception that proves the rule: they can never be detected in logs at all, because the cracking happens entirely on the adversary's own machine, against a stolen hash database — the real login system is never touched.
4.1.DSkill

Assessing Risk: High, Moderate, Low

Risk from a device vulnerability depends on what's at stake and how likely exploitation actually is.

LevelExample
HighAn organization hasn't installed a patch for a known critical vulnerability on its email server
ModerateA water treatment plant's pump controls allow remote username/password access without MFA
LowAn employee's laptop has an open Telnet port with minimal potential impact
💡Notice that risk level tracks two things at once: how sensitive or critical the affected system is, and how weak the actual protection is. A critical system with strong protection and a low-value system with a wide-open door can land at similar risk levels for very different reasons.
Skill

Documenting a Compromised Server's Risk

ExampleGuided Example — Writing Up the Finding

During an investigation, you find Event 1102 in the security log, followed shortly by a 4688 entry showing a process launched from C:\Users\Public\svc_update.exe — a path that doesn't match any legitimate installed software.

Step 1Identify
An audit log clear event (1102) immediately followed by a process launch from an unrecognized, non-standard path (4688).
← Back to Activity 2.3.3Next: Project 2.3.4 →Find the Exploits.