ESXi Virtual Machine Snapshot Removed
editESXi Virtual Machine Snapshot Removed
editDetects removal of all snapshots for an ESXi virtual machine. Snapshots are on-host recovery points for a guest. Removing all of them deletes those recovery points, so the virtual machine cannot be reverted to an earlier disk state.
Rule type: query
Rule indices:
- logs-vsphere.log-*
Severity: high
Risk score: 73
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Domain: Endpoint
- Data Source: VMware vSphere
- Use Case: Threat Detection
- Tactic: Impact
- Resources: Investigation Guide
- Rule Type: Custom Query (KQL)
- Platform: VMware ESXi
- Threat: Ransomware
Version: 1
Rule authors:
- Elastic
Rule license: Elastic License v2
Investigation guide
editTriage and analysis
Investigating ESXi Virtual Machine Snapshot Removed
Snapshots are the local recovery point on a datastore. snapshot.removeall deletes them for one VM id. Ransomware wraps that command in a loop over every VM.
Possible investigation steps
- Read the VM id in message. A loop that calls removeall for every id from getallvms is higher severity than one VM.
- Check whether VM processes were killed or disks were enumerated in the same session.
- Ask the backup or virtualization owner whether snapshot consolidation was underway.
False positive analysis
Backup products and administrators delete snapshots after a successful consolidate. Match the account and the change ticket before closing the alert.
Response and remediation
- If removal was not approved, isolate the host and stop the shell session.
- Restore affected VMs from an off-host backup. Datastore snapshots removed by this command are gone.
- Preserve shell history and hostd logs.
Setup
editSetup
This rule requires ESXi host logs collected by the Elastic vSphere integration: https://www.elastic.co/docs/reference/integrations/vsphere
Rule query
editdata_stream.dataset: "vsphere.log" and ( message: "snapshot.removeall" )
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Impact
- ID: TA0040
- Reference URL: https://attack.mitre.org/tactics/TA0040/
-
Technique:
- Name: Inhibit System Recovery
- ID: T1490
- Reference URL: https://attack.mitre.org/techniques/T1490/