April 28, 2026 · 9 min read · Incident ResponsePlaybookOps

Incident Response Checklist: The First 24 Hours

The first day after detecting an incident decides whether you contain damage—or multiply it. This checklist keeps small teams focused under pressure.

Hour 0–2: Confirm + contain

Validate alert with evidence (logs, endpoint behavior, account activity)
Isolate affected systems/accounts without wiping evidence
Revoke exposed credentials and force key/session rotation

Hour 2–6: Preserve evidence

Capture logs, timestamps, and relevant snapshots
Document all actions taken (who/what/when)
Avoid “quick cleanup” that destroys investigation trail

Hour 6–12: Scope impact

Identify affected assets, users, and data classes
Map entry path and lateral movement signs
Prioritize recovery sequence by business criticality

Hour 12–24: Communicate + recover

Publish internal status cadence (even if brief)
Apply fixes with validation checkpoints
Plan customer/legal notifications where required

What not to do

Don’t silently restart everything and hope it disappears
Don’t delete compromised accounts before evidence capture
Don’t send speculative root-cause updates as facts

Build your lightweight IR routine

EdgeIQ monitoring + reporting can reduce mean time to detection and give you cleaner response data when incidents hit.

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