Incident: Analyst-selected activity for investigation

Verdict

This system does not compute a confidence score for its verdict. The evidence basis is a count of what was checked, not a measure of how likely the verdict is.

Investigation Tree

• Initial alert: Analyst-selected activity for investigation
  rules ANALYST-SEED; 1 seed event(s): wlb-process-0001058
• ↓
• ATH investigation (engine d1)
  • process_tree device='CLIENT1', pid=9284, process_guid='sysmon:416dd0c5-12ee-6770-2904-000000000c00'
    model's reason “Need to inspect child processes of firefox.exe (pid 9284) to determine if any suspicious commands or scripts were executed.”
    new events 2 retrieved; shown: wlb-process-0001057, wlb-process-0001055
  stopped: model chose no probe
• ↓
• Verdict: Benign

Reasoning Summary

Quoted text below is model output, reproduced verbatim. It is not verified fact: the checks applied to it cover the event ids it cites and any typed premises it declared, not what its sentences assert. Each cited id is marked by whether it names an event the investigation retrieved.

1. model label benign verifier: accepted

   model wrote
   The observed process is a standard user-initiated launch of Firefox to open a local PDF file. The command line shows no suspicious arguments, and the process tree confirms no malicious children or network exfiltration occurred.

   Cited: wlb-process-0001058 (retrieved)

Executive Summary

This report covers CASE-SEED, correlating 1 detection finding(s) across 1 host(s) (CLIENT1) and 1 account(s) (client1) between 15:02:06 and 15:02:06 UTC on 2024-12-28. 5 statement(s) below are directly established by telemetry, 4 are evidence-supported inferences, and 0 are explicitly unverified hypotheses requiring analyst confirmation. This report does not authorise or perform any response action. All recommendations below require human review before action is taken.

Attack Timeline

Findings

Confirmed (FACT) (5)

• Confirmed: Event wlb-process-0001058 records process identity sysmon:416dd0c5-12ee-6770-2904-000000000c00.
  Evidence: wlb-process-0001058
• Confirmed: Event wlb-process-0001055 records process identity sysmon:416dd0c5-12ed-6770-2604-000000000c00.
  Evidence: wlb-process-0001055
• Confirmed: Event wlb-process-0001057 records process identity sysmon:416dd0c5-12ee-6770-2804-000000000c00.
  Evidence: wlb-process-0001057
• Confirmed: Process event wlb-process-0001057 identifies the instance in wlb-process-0001055 as its parent.
  Evidence: wlb-process-0001055, wlb-process-0001057
• Confirmed: Process event wlb-process-0001058 identifies the instance in wlb-process-0001057 as its parent.
  Evidence: wlb-process-0001057, wlb-process-0001058

Assessed (INFERENCE) (4)

• Assessed: Unverified summary: ANALYST-SEED (MEDIUM) on CLIENT1 under account client1: Analyst-selected activity for investigation. An analyst selected these events for review. The selection says where to look; it is not a detection and carries no verdict.
  Evidence: wlb-process-0001058
• Assessed: Unverified summary: The case's cited telemetry comprises 1 of 1 event(s), from 2024-12-28T15:02:06+00:00 to 2024-12-28T15:02:06+00:00.
  Evidence: wlb-process-0001058
• Assessed: Unverified summary: On CLIENT1, firefox.exe (PID 9284) ran under account client1 with execution chain - -> cmd.exe -> firefox.exe -> firefox.exe, spawning no observed child process. Resolution: identity.
  Evidence: wlb-process-0001058, wlb-process-0001057, wlb-process-0001055
• Assessed: [benign] The observed process is a standard user-initiated launch of Firefox to open a local PDF file. The command line shows no suspicious arguments, and the process tree confirms no malicious children or network exfiltration occurred.
  Evidence: wlb-process-0001058

Unconfirmed Hypotheses (0)

• None.

Recommended Next Steps

Investigative recommendations for a human analyst. No response action has been taken or is authorised by this report.

1. Retrieve email gateway or web-proxy logs to establish the initial access vector.
   Rationale: No detection in this case targets initial access, so the delivery mechanism (e.g. a phishing attachment) is inferred from process lineage rather than confirmed from delivery telemetry.
   Based on: MITRE ATT&CK tactic coverage gap: Initial Access
2. Escalate to a human analyst for validation before any remediation action is taken.
   Rationale: This system performs read-only investigation only. It has no capability to disable accounts, isolate hosts, or otherwise remediate, and this report is not authorisation to do so.
   Based on: system design constraint

Limitations & Scope

• Telemetry underlying this report came from: winlogbeat. Field coverage depends entirely on what the originating export or sensor captured; this project's canonical schema does not model every field a real EDR product exposes (e.g. file hashes, signer information, session identifiers), and any of those were dropped during normalization.
• ATT&CK mappings are interpretations of observed behaviour against a public taxonomy. They indicate that behaviour is consistent with a technique, not that an adversary performed it.
• Grouping confidence describes how strongly correlated findings are linked to each other, not whether an intrusion occurred.
• No evidence was found for the following ATT&CK tactics: Initial Access, Discovery, Credential Access, Lateral Movement, Collection, Exfiltration. Their absence may reflect that the activity did not occur, or that available telemetry cannot observe it.
• Typed predicates are checked against recorded telemetry; free-text interpretations are not semantically verified. Missing identity is not a confirmed process link, and recorded event order does not establish causation.
• disposition: benign
• evidence gap: none

Investigation Trace

Agents run: investigator:seed, investigator:probe, investigator:conclude; tool calls made: 3

• step 1: investigator:seed -- findings, cited rows, techniques
• step 2: investigator:probe -- P1 process_tree: Need to inspect child processes of firefox.exe (pid 9284) to determine if any suspicious commands or scripts were executed.
• conclude: 1 explanation(s) proposed, 0 with out-of-scope citations dropped; disposition benign
• conclude: accepted 1, rejected 0
• stop -- model chose no probe
• evidence verification: 5 checked observations; 3 summaries reclassified

Evidence Appendix

All 3 telemetry events underlying this report, chronologically.