These rules flag services with significant month-over-month cost increases so you can investigate unexpected spend before it compounds.
| Rule ID | Scan Type | Severity | Name |
|---|---|---|---|
| CLDBRN-AWS-COSTEXPLORER-1 | Discovery | Medium | Cost Explorer Full Month Cost Changes |
CLDBRN-AWS-COSTEXPLORER-1
Cost Explorer Full Month Cost Changes
Scan type: Discovery
Severity: Medium
What it checks
Flags AWS services whose cost increased by more than $10 between the last two full calendar months. This surfaces services where spend is trending upward so you can investigate whether the increase is expected (new workloads, traffic growth) or accidental (misconfigured resources, forgotten experiments).
Why it matters
Cost anomalies caught early are cheap to fix. A $15/month increase this month might indicate a misconfigured resource that will cost $180+ over a year if left unaddressed. Reviewing month-over-month changes at the service level is one of the fastest ways to catch cost drift.
What triggers a finding
Both conditions must be true:
- The service had non-zero cost in the previous full month (
previousMonthCost > 0) - The cost increase between the two months exceeds $10
How to remediate
- Open Cost Explorer in the AWS Console and filter by the flagged service
- Drill into the specific usage type to identify what changed (new instances, increased data transfer, storage growth, etc.)
- If the increase is unintentional, address the root cause: terminate unused resources, right-size instances, or adjust configurations
- Set up a Cost Anomaly Detection monitor for the service to catch future spikes earlier
See Also
- CLI discover command - scan live cost data
- SDK Reference - run discovery programmatically