IT Toolbox

Cyber Incident Center

Incident response / Defensive

Cyber Incident Center

Structure containment, evidence, the timeline and incident-response actions without performing offensive actions.

Timeline

Incident information

1

Containment

Reduce impact without destroying useful evidence.

2

Evidence

Preserve timestamps, logs, headers and IOCs.

3

Accounts

Revoke compromised sessions and secrets.

4

Backups

Protect backup copies before the attacker can reach them.

5

Timeline

Record every action and decision.

6

Lessons learned

Fix root causes after recovery.

Important: this tool helps structure a defensive response. For a major incident, quickly involve the appropriate security, legal and compliance teams.
Field troubleshooting

Center mission

8 playbooks

Contain and document an incident without destroying evidence: scope it, isolate when needed, protect identities, preserve logs and prepare escalation.

Quick triage

  • Record time, alert source and initial indicators before deleting anything.
  • Scope impact: account, endpoint, server, tenant or network.
  • If dangerous activity is active, isolate asset according to procedure.
  • Preserve logs, headers, hashes, screenshots and alert IDs.
  • Use a clean endpoint for password/admin changes.

Decision tree

Phishing with no user action→

Preserve email, block IOC and search for received copies.

Compromised account→

Revoke sessions, secure identity then hunt for persistence.

Active malware on endpoint→

Network-isolate, preserve evidence and use approved EDR/AV.

Ransomware / propagation→

Prioritize containment, identity, backups and incident command.

Intervention playbooks

Start read-only, collect evidence, then change one variable at a time.

01Reported phishingRead-only
Symptom

User receives suspicious email with link, attachment or urgent request.

Checks

  • Preserve original message and full headers.
  • Determine whether link opened, attachment executed or credentials entered.
  • Search sender, domain, URL and hash across scope.

Commands / evidence

Get-FileHash <attachment> -Algorithm SHA256Resolve-DnsName <domain>Get-MpThreatDetection

Expected result

User exposure level is known and IOCs are preserved.

Corrective actions

  • Block IOCs via approved tools and remove copies after evidence preservation.
  • If credentials entered, immediately switch to compromised-account playbook.

Escalate when

Attachment executed, token stolen or campaign affects multiple users.

02Compromised accountIntrusive / escalation
Symptom

Abnormal sign-ins, fraudulent MFA, mailbox rules or unauthorized sends.

Checks

  • Collect sign-in logs, IP, device and time.
  • Look for mailbox rules, forwarding, OAuth apps and added MFA methods.
  • Determine whether admin privileges or lateral access exist.

Commands / evidence

Get-MgUserAuthenticationMethod -UserId <UPN>Get-InboxRule -Mailbox <UPN>Get-MgUser -UserId <UPN>

Expected result

Sessions and persistence mechanisms are identified before remediation.

Corrective actions

  • Revoke sessions/tokens and change secret from clean endpoint.
  • Remove unauthorized rules/apps/MFA after evidence collection.

Escalate when

Admin account, sensitive-data access or multiple correlated accounts.

03Malware detected on endpointIntrusive / escalation
Symptom

EDR/Defender alerts on malicious executable, script or behavior.

Checks

  • Preserve name, path, hash, parent process and user.
  • Check network connections and other detections.
  • Assess propagation or presence on other endpoints.

Commands / evidence

Get-MpThreatDetectionGet-Process | Sort-Object StartTime -Descending | Select -First 30Get-NetTCPConnection -State Established

Expected result

Asset and behavior are identified, endpoint contained and sufficient evidence preserved.

Corrective actions

  • Isolate via EDR or network if activity is active.
  • Use approved EDR/AV remediation after initial collection.

Escalate when

Persistence, privilege escalation, C2 or lateral movement suspected.

04Suspicious PowerShellRead-only
Symptom

Alert on powershell.exe, encoded command, download or unusual execution.

Checks

  • Identify command line, parent, user and context.
  • Read PowerShell Operational/ScriptBlock logs if enabled.
  • Correlate URL, created file and network connections.

Commands / evidence

Get-WinEvent -LogName Microsoft-Windows-PowerShell/Operational -MaxEvents 100Get-CimInstance Win32_Process | ? Name -eq "powershell.exe" | Select ProcessId,ParentProcessId,CommandLineGet-NetTCPConnection -State Established

Expected result

Command and parent chain explain whether activity is administrative or malicious.

Corrective actions

  • Preserve script/command line and hashes of associated files.
  • Isolate if malicious behavior or unauthorized download/execution is present.

Escalate when

Obfuscated command, credential theft, C2 or execution on multiple hosts.

05Ransomware / active encryptionIntrusive / escalation
Symptom

Files renamed/encrypted, ransom note or mass activity.

Checks

  • Identify first hosts and start time.
  • Check shares, accounts and propagation paths.
  • Immediately protect backups/immutability.

Commands / evidence

Get-SmbSessionGet-SmbOpenFileGet-WinEvent -LogName Security -MaxEvents 200

Expected result

Propagation is contained and at least one healthy data copy remains isolated.

Corrective actions

  • Isolate active hosts and compromised accounts per incident procedure.
  • Do not restore before eradication and validation of a clean copy.

Escalate when

Still active, servers/AD affected, backups threatened or possible regulatory obligation.

06Suspected data exfiltrationIntrusive / escalation
Symptom

Unusual upload, large outbound volume, suspicious archive or mass data access.

Checks

  • Define user, machine, destination and volume.
  • Preserve proxy/firewall/EDR/cloud audit logs.
  • Identify files or spaces accessed.

Commands / evidence

Get-NetTCPConnection -State EstablishedGet-WinEvent -LogName Security -MaxEvents 200Get-Process | Sort-Object CPU -Descending | Select -First 30

Expected result

Suspicious flow is bounded by time, volume, destination and identity.

Corrective actions

  • Contain account/endpoint based on confidence without erasing logs.
  • Preserve evidence for legal/security analysis.

Escalate when

Sensitive data, confirmed external destination or contractual/regulatory impact.

07Lost or stolen endpointIntrusive / escalation
Symptom

Corporate endpoint is physically uncontrolled with potential data access.

Checks

  • Confirm BitLocker/FileVault encryption and last check-in.
  • Identify accounts/tokens present and privilege level.
  • Check MDM capability to lock/retire data.

Commands / evidence

Get-MgDevice -Filter "displayName eq '<PC>'"Get-BitLockerVolumedsregcmd /status

Expected result

Risk is qualified by encryption, MDM management and identity exposure.

Corrective actions

  • Revoke sensitive sessions and apply MDM action per policy.
  • Keep hardware ID and loss/theft report.

Escalate when

Unencrypted disk, sensitive admin/local account or regulated data.

08Exposed service / leaked credentialIntrusive / escalation
Symptom

Unexpected public port, published secret or external exposure alert.

Checks

  • Confirm exposure from an authorized external source.
  • Identify service/secret owner and exposure duration.
  • Search authentications or access during exposure window.

Commands / evidence

Test-NetConnection <public-host> -Port <port>Get-NetTCPConnection -State ListenGet-WinEvent -LogName Security -MaxEvents 200

Expected result

Real exposure, window and potential use are documented before closure/rotation.

Corrective actions

  • Close unnecessary exposure and rotate secret from clean environment.
  • Search for secret reuse across systems.

Escalate when

Unauthorized access observed, privileged secret or critical Internet-facing service.

End-of-intervention checklist

  • Preserve timeline and evidence before closure.
  • Verify containment left no known persistence.
  • Confirm required identity rotation/revocation.
  • Validate backups and post-incident monitoring.
  • Document actions and return-to-normal criteria.

Continue in BAOI

Related cheat sheetPowerShell — collection and checks IT toolsCalculate, inspect or generate without leaving the workflow. ProceduresFollow a controlled implementation procedure. Known failuresCross-check the symptom with known failure patterns.
♡ 0