PBQ

Log Analysis — Identify Infection Origin & Classify Hosts

SY0-701 Obj 4.3 · Incident Response
A malware incident has been reported on the corporate network. Four hosts are shown below. Review each host's event log carefully and classify each as:
  Origin — the host that first introduced the infection
  Infected — compromised by the origin host
  Clean — no signs of compromise

Use timestamps, SMB connections, USB events, and AV alerts to make your determination.

Click a classification button for each host

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WORKSTATION-A
192.168.1.101
[08:12:04] User login: jsmith
[08:15:22] AV scan: No threats found
[08:30:01] File access: reports.xlsx
[09:01:15] User logout: jsmith
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WORKSTATION-B
192.168.1.102
[07:55:10] User login: mlee
[08:02:33] USB device inserted: Unknown
[08:03:01] Process created: malware.exe
[08:03:45] SMB outbound → 192.168.1.103
[08:04:10] SMB outbound → 192.168.1.104
[08:05:22] AV alert: Trojan.GenericKD blocked
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WORKSTATION-C
192.168.1.103
[08:01:00] User login: atran
[08:04:05] SMB inbound ← 192.168.1.102
[08:04:18] Process created: svchost_fake.exe
[08:06:40] AV alert: Worm.SMB.Lateral – quarantine FAILED
[08:07:00] Outbound C2 → 203.0.113.50:443
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SERVER-D
192.168.1.104
[08:00:00] Service started: IIS
[08:04:22] SMB inbound ← 192.168.1.102
[08:04:55] File written: C:\Windows\Temp\update.bat
[08:05:30] AV alert: Trojan.GenericKD – quarantined
[08:05:31] AV quarantine: SUCCESS
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