Detect Malicious Usage of Recovery Tools to Delete Backup Files

Status: available
Severity: high
Time window: 1h
Source: github.com/Azure/Azure-Sentinel

This analytic rule detects usage of recovery tools vssadmin, wbadmin, wmic and bcedit to delete backup files or change recovery configuration. Adversaries may use these tools to delete shadow copies and backup files to prevent recovery of files. https://attack.mitre.org/techniques/T1490/

MITRE ATT&CK coverage

Tactic	Techniques
Impact	`T1490` Inhibit System Recovery

Event coverage

Provider	Event	Title
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 kusto

id: 259de2c1-c546-4c6d-a17c-df639722f4d7
name: Detect Malicious Usage of Recovery Tools to Delete Backup Files
description: |
  This analytic rule detects usage of recovery tools vssadmin, wbadmin, wmic and bcedit to delete backup files or change recovery configuration. Adversaries may use these tools to delete shadow copies and backup files to prevent recovery of files.
  https://attack.mitre.org/techniques/T1490/
severity: High
status: Available 
tags:
  - Schema: _ASim_ProcessEvent
    SchemaVersion: 0.1.4
requiredDataConnectors:
  - connectorId: CrowdStrikeFalconEndpointProtection
    dataTypes: 
      - CommonSecurityLog
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - SecurityAlert
  - connectorId: SentinelOne
    dataTypes:
      - SentinelOne_CL
  - connectorId: VMwareCarbonBlack
    dataTypes:
      - CarbonBlackEvents_CL
  - connectorId: CiscoSecureEndpoint
    dataTypes:
      - CiscoSecureEndpoint_CL
  - connectorId: TrendMicroApexOne
    dataTypes:
      - TMApexOneEvent
  - connectorId: TrendMicroApexOneAma
    dataTypes:
      - TMApexOneEvent
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Impact
relevantTechniques:
  - T1490
query: |
  _ASim_ProcessEvent
  | where TargetProcessFilename has_any ('vssadmin.exe', 'wbadmin.exe', 'wmic.exe')
  | where CommandLine has_all ('delete', 'shadow')
  | union isfuzzy=True 
      (_ASim_ProcessEvent
      | where TargetProcessFilename =~ 'bcedit.exe'
      | where CommandLine has_all ('/set', 'recoveryenabled no')
      )
  | project
      TimeGenerated,
      DvcHostname,
      DvcIpAddr,
      DvcDomain,
      TargetUsername,
      TargetUsernameType,
      TargetProcessName,
      TargetProcessId,
      CommandLine
  | extend Username = iff(tostring(TargetUsernameType) == 'Windows', tostring(split(TargetUsername, '\\')[1]), TargetUsername)
  | extend NTDomain = iff(tostring(TargetUsernameType) == 'Windows', tostring(split(TargetUsername, '\\')[0]), TargetUsername)
  | extend Username = iff(tostring(TargetUsernameType) == 'UPN', tostring(split(TargetUsername, '@')[0]), Username)
  | extend UPNSuffix = iff(tostring(TargetUsernameType) == 'UPN', tostring(split(TargetUsername, '@')[1]), '')
entityMappings:
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: DvcHostname
      - identifier: DnsDomain
        columnName: DvcDomain
      - identifier: NTDomain
        columnName: NTDomain
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: DvcIpAddr
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: Username
      - identifier: UPNSuffix
        columnName: UPNSuffix
      - identifier: NTDomain
        columnName: NTDomain
  - entityType: Process
    fieldMappings:
      - identifier: ProcessId
        columnName: TargetProcessId
      - identifier: CommandLine
        columnName: CommandLine
eventGroupingSettings:
  aggregationKind: AlertPerResult
alertDetailsOverride:
  alertDisplayNameFormat: "Tool {{TargetProcessName}} used to delete backup files on {{DvcHostname}} by {{TargetUsername}}"
  alertDescriptionFormat: "A system tool {{TargetProcessName}} ProcessId: ({{TargetProcessId}}) with {{CommandLine}} used to delete backup files."
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: `source`

_ASim_ProcessEvent

Stage 2: `where`

| where TargetProcessFilename has_any ('vssadmin.exe', 'wbadmin.exe', 'wmic.exe')

Stage 3: `where`

| where CommandLine has_all ('delete', 'shadow')

Stage 4: `union`

| union isfuzzy=True

Stage 5: `source`

_ASim_ProcessEvent

Stage 6: `where`

| where TargetProcessFilename =~ 'bcedit.exe'

Stage 7: `where`

| where CommandLine has_all ('/set', 'recoveryenabled no')

Stage 8: `project`

| project
    TimeGenerated,
    DvcHostname,
    DvcIpAddr,
    DvcDomain,
    TargetUsername,
    TargetUsernameType,
    TargetProcessName,
    TargetProcessId,
    CommandLine

Stage 9: `extend` (4 consecutive steps)

| extend Username = iff(tostring(TargetUsernameType) == 'Windows', tostring(split(TargetUsername, '\\')[1]), TargetUsername)
| extend NTDomain = iff(tostring(TargetUsernameType) == 'Windows', tostring(split(TargetUsername, '\\')[0]), TargetUsername)
| extend Username = iff(tostring(TargetUsernameType) == 'UPN', tostring(split(TargetUsername, '@')[0]), Username)
| extend UPNSuffix = iff(tostring(TargetUsernameType) == 'UPN', tostring(split(TargetUsername, '@')[1]), '')

Username =

ifTargetUsernameType == "Windows"tostring(split(TargetUsername, '\\')[1])

elseTargetUsername

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`CommandLine`	match	`/set` corpus 6 (splunk 5, kusto 1) `delete` corpus 23 (sigma 16, splunk 6, kusto 1) `recoveryenabled no` `shadow` corpus 7 (sigma 3, splunk 2, elastic 1, kusto 1)
`TargetProcessFilename`	eq	`bcedit.exe`
`TargetProcessFilename`	match	`vssadmin.exe` `wbadmin.exe` `wmic.exe`

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

Field	Source
`CommandLine`	`project`
`DvcDomain`	`project`
`DvcHostname`	`project`
`DvcIpAddr`	`project`
`TargetProcessId`	`project`
`TargetProcessName`	`project`
`TargetUsername`	`project`
`TargetUsernameType`	`project`
`TimeGenerated`	`project`
`Username`	`extend`
`NTDomain`	`extend`
`UPNSuffix`	`extend`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)

Detect Malicious Usage of Recovery Tools to Delete Backup Files

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `union`

Stage 5: `source`

Stage 6: `where`

Stage 7: `where`

Stage 8: `project`

Stage 9: `extend` (4 consecutive steps)

Indicators

Output fields

Keyboard shortcuts

Search operators

Detect Malicious Usage of Recovery Tools to Delete Backup Files

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Stage 1: source

Stage 2: where

Stage 3: where

Stage 4: union

Stage 5: source

Stage 6: where

Stage 7: where

Stage 8: project

Stage 9: extend (4 consecutive steps)

Indicators

Output fields

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `union`

Stage 5: `source`

Stage 6: `where`

Stage 7: `where`

Stage 8: `project`

Stage 9: `extend` (4 consecutive steps)