Imminent Ransomware

Status: available
Severity: high
Time window: 6h
Group by: BatExclusion, BootTampering, DefenderTamp, DisableControlledFolderAccess, Dvc, DvcId, ExeExclusion, NetshFirewallTampering, ScDeleteDefend, SchTasks, StartUpExclusionPath, TimeGenerated
Source: github.com/Azure/Azure-Sentinel

This query checks for a series of commands that are commonly used by attackers to disable security tools and system recovery tools before deploying Macaw ransomware in an organization.

MITRE ATT&CK coverage

Tactic	Techniques
Persistence	`T1547` Boot or Logon Autostart Execution
Defense Impairment	`T1685` Disable or Modify Tools

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation
Sysmon	Event ID 5: Process terminated
Security-Auditing	Event ID 4688: A new process has been created.
Security-Auditing	Event ID 4689: A process has exited.

Rule body

id: bb46dd86-e642-48a4-975c-44f5ac2b5033
name: Imminent Ransomware
description: |
  This query checks for a series of commands that are commonly used by attackers to disable security tools and system recovery tools before deploying Macaw ransomware in an organization.
severity: High
status: Available
requiredDataConnectors: []
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - DefenseEvasion
  - Persistence
relevantTechniques:
  - T1562
  - T1547
tags:
  - Schema: _ASim_ProcessEvent
    SchemaVersion: 0.1.4
  - Ransomware Campaign
  - Macaw Ransomware
query: |
  _ASim_ProcessEvent 
  // Pivot on specific commands 
  | where CommandLine has_any("-ExclusionPath", "Set-MpPreference", "advfirewall", "-ExclusionExtension", 
  "-EnableControlledFolderAccess", "windefend", "onstart", "bcdedit", "Startup") 
  // Making list of found commands 
  | summarize CommandLine = make_set(CommandLine, 10000) by DvcId, Dvc, bin(TimeGenerated, 6h) 
  // Extending columns for later aggregration, based on TTP
  | extend StartUpExclusionPath = iff(CommandLine has_all("-ExclusionPath", "Startup"), 1, 0) 
  | extend DefenderTamp = iff(CommandLine has "Set-MpPreference" 
  and CommandLine has_any( 
  "-SevereThreatDefaultAction 6" 
  "-HighThreatDefaultAction 6", 
  "-ModerateThreatDefaultAction 6", 
  "-LowThreatDefaultAction 6" 
  "-ScanScheduleDay 8"), 1, 0) 
  | extend NetshFirewallTampering = iff(CommandLine has_all( "netsh", "advfirewall", "allprofiles state off"), 1, 0) 
  | extend BatExclusion = iff(CommandLine has_all("-ExclusionExtension", ".bat"), 1, 0) 
  | extend ExeExclusion = iff(CommandLine has_all("-ExclusionExtension", ".exe"), 1, 0) 
  | extend DisableControlledFolderAccess = iff(CommandLine has_all("-EnableControlledFolderAccess", "Disabled"), 1, 0) 
  | extend ScDeleteDefend = iff(CommandLine has_all("sc", "delete", "windefend"), 1, 0) 
  | extend BootTampering = iff(CommandLine has_all("bcdedit", "default") and CommandLine has_any ("recoveryenabled No", "bootstatuspolicy ignoreallfailures"), 1, 0) 
  | extend SchTasks = iff(CommandLine has_all("/sc", "onstart", "system", "/create", "/delay"), 1, 0) 
  // Summarizing found commands 
  | summarize by NetshFirewallTampering ,BatExclusion, ExeExclusion, DisableControlledFolderAccess, ScDeleteDefend, SchTasks, BootTampering, DefenderTamp, StartUpExclusionPath, DvcId, Dvc, TimeGenerated 
  // Adding up each piece of evidence 
  | extend EvidenceCount = NetshFirewallTampering + BatExclusion + ExeExclusion + DisableControlledFolderAccess + ScDeleteDefend + SchTasks + BootTampering + DefenderTamp + StartUpExclusionPath 
  | where EvidenceCount > 4
  | extend HostName = iff(Dvc has '.', substring(Dvc, 0, indexof(Dvc, '.')), Dvc)
  | extend DnsDomain = iff(Dvc has '.', substring(Dvc, indexof(Dvc, '.') + 1), "")
entityMappings:
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: Dvc
      - identifier: HostName
        columnName: HostName
      - identifier: DnsDomain
        columnName: DnsDomain
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: `source`

_ASim_ProcessEvent

Stage 2: `where`

| where CommandLine has_any("-ExclusionPath", "Set-MpPreference", "advfirewall", "-ExclusionExtension", 
"-EnableControlledFolderAccess", "windefend", "onstart", "bcdedit", "Startup")

Stage 3: `summarize`

| summarize CommandLine = make_set(CommandLine, 10000) by DvcId, Dvc, bin(TimeGenerated, 6h)

Stage 4: `extend` (9 consecutive steps)

| extend StartUpExclusionPath = iff(CommandLine has_all("-ExclusionPath", "Startup"), 1, 0)
| extend DefenderTamp = iff(CommandLine has "Set-MpPreference" 
and CommandLine has_any( 
"-SevereThreatDefaultAction 6" 
"-HighThreatDefaultAction 6", 
"-ModerateThreatDefaultAction 6", 
"-LowThreatDefaultAction 6" 
"-ScanScheduleDay 8"), 1, 0)
| extend NetshFirewallTampering = iff(CommandLine has_all( "netsh", "advfirewall", "allprofiles state off"), 1, 0)
| extend BatExclusion = iff(CommandLine has_all("-ExclusionExtension", ".bat"), 1, 0)
| extend ExeExclusion = iff(CommandLine has_all("-ExclusionExtension", ".exe"), 1, 0)
| extend DisableControlledFolderAccess = iff(CommandLine has_all("-EnableControlledFolderAccess", "Disabled"), 1, 0)
| extend ScDeleteDefend = iff(CommandLine has_all("sc", "delete", "windefend"), 1, 0)
| extend BootTampering = iff(CommandLine has_all("bcdedit", "default") and CommandLine has_any ("recoveryenabled No", "bootstatuspolicy ignoreallfailures"), 1, 0)
| extend SchTasks = iff(CommandLine has_all("/sc", "onstart", "system", "/create", "/delay"), 1, 0)

StartUpExclusionPath =

ifCommandLine has "-ExclusionPath" and CommandLine has "Startup"1

else0

Stage 5: `summarize`

| summarize by NetshFirewallTampering ,BatExclusion, ExeExclusion, DisableControlledFolderAccess, ScDeleteDefend, SchTasks, BootTampering, DefenderTamp, StartUpExclusionPath, DvcId, Dvc, TimeGenerated

Stage 6: `extend`

| extend EvidenceCount = NetshFirewallTampering + BatExclusion + ExeExclusion + DisableControlledFolderAccess + ScDeleteDefend + SchTasks + BootTampering + DefenderTamp + StartUpExclusionPath

Stage 7: `where`

| where EvidenceCount > 4

Stage 8: `extend`

| extend HostName = iff(Dvc has '.', substring(Dvc, 0, indexof(Dvc, '.')), Dvc)

HostName =

ifDvc has "."substring(Dvc, 0, indexof(Dvc, '.'))

elseDvc

Stage 9: `extend`

| extend DnsDomain = iff(Dvc has '.', substring(Dvc, indexof(Dvc, '.') + 1), "")

DnsDomain =

ifDvc has "."substring(Dvc, (indexof(Dvc, '.') + 1))

else""

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`-EnableControlledFolderAccess` transforms: `term` `-ExclusionExtension` transforms: `term` `-ExclusionPath` transforms: `term` corpus 3 (kusto 2, elastic 1) `Set-MpPreference` transforms: `term` corpus 7 (sigma 3, splunk 2, elastic 1, kusto 1) `Startup` transforms: `term` corpus 3 (sigma 2, kusto 1) `advfirewall` transforms: `term` corpus 7 (sigma 6, kusto 1) `bcdedit` transforms: `term` `onstart` transforms: `term` corpus 2 (sigma 1, kusto 1) `windefend` transforms: `term` corpus 5 (sigma 3, elastic 1, kusto 1)	`field:"CommandLine" kind:match`
`EvidenceCount`	gt	`4`	`field:"EvidenceCount" kind:gt value:"4"`

Output fields

These fields are emitted when the rule matches.

Field	Source
`BatExclusion`	`summarize`
`BootTampering`	`summarize`
`DefenderTamp`	`summarize`
`DisableControlledFolderAccess`	`summarize`
`Dvc`	`summarize`
`DvcId`	`summarize`
`ExeExclusion`	`summarize`
`NetshFirewallTampering`	`summarize`
`ScDeleteDefend`	`summarize`
`SchTasks`	`summarize`
`StartUpExclusionPath`	`summarize`
`TimeGenerated`	`summarize`
`EvidenceCount`	`extend`
`HostName`	`extend`
`DnsDomain`	`extend`

Imminent Ransomware

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 1: source

Stage 2: where

Stage 3: summarize

Stage 4: extend (9 consecutive steps)

Stage 5: summarize

Stage 6: extend

Stage 7: where

Stage 8: extend

Stage 9: extend