Detect Registry Run Key Creation/Modification

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

This analytic rule detects any registry value or key creation in the registry run keys. This could be an indication of a persistence attempt by an adversary.

MITRE ATT&CK coverage

Tactic	Techniques
Persistence	`T1112` Modify Registry, `T1547` Boot or Logon Autostart Execution
Privilege Escalation	`T1547` Boot or Logon Autostart Execution

Event coverage

Provider	Event/ActionType	Title
Sysmon	Event ID 12	RegistryEvent (Object create and delete)
Sysmon	Event ID 13	RegistryEvent (Value Set)
Sysmon	Event ID 14	RegistryEvent (Key and Value Rename)
Security-Auditing	Event ID 4657	A registry value was modified.
Security-Auditing	Event ID 4660	An object was deleted.
Security-Auditing	Event ID 4663	An attempt was made to access an object.
Defender-DeviceRegistryEvents	RegistryKeyDeleted	Registry key deleted
Defender-DeviceRegistryEvents	RegistryValueSet	Registry value set
Defender-DeviceRegistryEvents	RegistryValueDeleted	Registry value deleted
Defender-DeviceRegistryEvents	RegistryKeyRenamed	Registry key renamed

Rule body kusto

id: dd041e4e-1ee2-41ec-ba4e-82a71d628260
name: Detect Registry Run Key Creation/Modification
description: |
  This analytic rule detects any registry value or key creation in the registry run keys. This could be an indication of a persistence attempt by an adversary.
severity: Medium
status: Available 
tags:
  - Schema: _ASim_RegistryEvent
    SchemaVersion: 0.1.2
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:
  - Persistence
  - PrivilegeEscalation
  - DefenseEvasion
relevantTechniques:
  - T1547
  - T1112
query: |
  // List of startup registry keys to monitor
  let startupRegistryList = dynamic([
      'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run',
      'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Run',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnceEx',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce',
      'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices',
      'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run',
      'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Userinit',
      'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Shell',
      'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Windows'
    ]);
  _ASim_RegistryEvent
  | where EventType in ('RegistryValueSet', 'RegistryKeyCreated') and RegistryKey has_any (startupRegistryList)
  | project
      TimeGenerated,
      DvcHostname,
      ActorUsername,
      ActorUsernameType,
      ActingProcessId,
      ActingProcessName,
      ActingProcessCommandLine,
      RegistryKey,
      RegistryValue,
      RegistryValueType,
      RegistryValueData
  | extend HostName = tostring(split(DvcHostname, '.')[0])
  | extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))
  | extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[1]), ActorUsername)
  | extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[0]), ActorUsername)
  | extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)
  | extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')
  | extend RegHive = tostring(split(RegistryKey, '\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\'), 1, -1), '\\')) 
entityMappings:
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: HostName
      - identifier: DnsDomain
        columnName: DnsDomain
      - identifier: NTDomain
        columnName: NTDomain
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: Username
      - identifier: UPNSuffix
        columnName: UPNSuffix
      - identifier: NTDomain
        columnName: NTDomain
  - entityType: Process
    fieldMappings:
      - identifier: ProcessId
        columnName: ActingProcessId
      - identifier: CommandLine
        columnName: ActingProcessCommandLine
  - entityType: RegistryKey
    fieldMappings:
      - identifier: Hive
        columnName: RegHive
      - identifier: Key
        columnName: RegKey
  - entityType: RegistryValue
    fieldMappings:
      - identifier: Name
        columnName: RegistryValue
      - identifier: Value
        columnName: RegistryValueData
      - identifier: ValueType
        columnName: RegistryValueType
eventGroupingSettings:
  aggregationKind: SingleAlert
alertDetailsOverride:
  alertDisplayNameFormat: "Registry Run Keys Modified on {{DvcHostname}} ({{DvcIpAddr}}) by ({{ActorUsername}})"
  alertDescriptionFormat: "Process {{ActingProcessName}} ProcessId: ({{ActingProcessId}}) modified registry run key {{RegistryKey}}."
version: 1.0.0
kind: Scheduled

Stages and Predicates

Let binding: `startupRegistryList`

let startupRegistryList = dynamic([
    'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run',
    'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Run',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnceEx',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce',
    'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices',
    'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run',
    'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Userinit',
    'HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Shell',
    'HKEY_CURRENT_USER\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Windows'
  ]);

Stage 1: `source`

_ASim_RegistryEvent

Stage 2: `where`

| where EventType in ('RegistryValueSet', 'RegistryKeyCreated') and RegistryKey has_any (startupRegistryList)

References startupRegistryList (defined above).

Stage 3: `project`

| project
    TimeGenerated,
    DvcHostname,
    ActorUsername,
    ActorUsernameType,
    ActingProcessId,
    ActingProcessName,
    ActingProcessCommandLine,
    RegistryKey,
    RegistryValue,
    RegistryValueType,
    RegistryValueData

Stage 4: `extend` (7 consecutive steps)

| extend HostName = tostring(split(DvcHostname, '.')[0])
| extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))
| extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[1]), ActorUsername)
| extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[0]), ActorUsername)
| extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)
| extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')
| extend RegHive = tostring(split(RegistryKey, '\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\'), 1, -1), '\\'))

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
`EventType`	in	`RegistryKeyCreated` transforms: `cased` `RegistryValueSet` transforms: `cased` corpus 4 (kusto 4)
`RegistryKey`	match	`HKEY_CURRENT_USER\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Windows` `HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run` `HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run` `HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce` `HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices` `HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Shell` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Userinit` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Run` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnceEx` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices` `HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce`

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
`ActingProcessCommandLine`	`project`
`ActingProcessId`	`project`
`ActingProcessName`	`project`
`ActorUsername`	`project`
`ActorUsernameType`	`project`
`DvcHostname`	`project`
`RegistryKey`	`project`
`RegistryValue`	`project`
`RegistryValueData`	`project`
`RegistryValueType`	`project`
`TimeGenerated`	`project`
`HostName`	`extend`
`DnsDomain`	`extend`
`Username`	`extend`
`NTDomain`	`extend`
`UPNSuffix`	`extend`
`RegHive`	`extend`
`RegKey`	`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 Registry Run Key Creation/Modification

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Let binding: `startupRegistryList`

Stage 1: `source`

Stage 2: `where`

Stage 3: `project`

Stage 4: `extend` (7 consecutive steps)

Indicators

Output fields

Keyboard shortcuts

Search operators

Detect Registry Run Key Creation/Modification

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Let binding: startupRegistryList

Stage 1: source

Stage 2: where

Stage 3: project

Stage 4: extend (7 consecutive steps)

Indicators

Output fields

Let binding: `startupRegistryList`

Stage 1: `source`

Stage 2: `where`

Stage 3: `project`

Stage 4: `extend` (7 consecutive steps)