Suspicious Process Injection from Office application

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

This query detects process injections using CreateRemoteThread, QueueUserAPC or SetThread context APIs, originating from an Office process (only Word/Excel/PowerPoint)that might contains macros. Performing process injection from a macro is a common technique by attackers to escape out of the Office process into something longer running.

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1204` User Execution

Event coverage

Provider	Event/ActionType	Title
Sysmon	Event ID 4	Sysmon service state changed
Sysmon	Event ID 5	Process terminated
Sysmon	Event ID 8	CreateRemoteThread
Defender-DeviceEvents	CreateRemoteThreadApiCall	CreateRemoteThread API call

Rule body kusto

id: a4d8e681-6f30-440a-a2f3-c312bc1389d0
name: Suspicious Process Injection from Office application
description: |
  This query detects process injections using CreateRemoteThread, QueueUserAPC or SetThread context APIs, originating from an Office process (only Word/Excel/PowerPoint)that might contains macros. Performing process injection from a macro is a common technique by attackers to escape out of the Office process into something longer running. 
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - DeviceEvents
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Execution
relevantTechniques:
  - T1204
query: |
  DeviceEvents 
  | where ActionType in ("CreateRemoteThreadApiCall", "QueueUserApcRemoteApiCall", "SetThreadContextRemoteApiCall")
  | where InitiatingProcessFileName in~ ("winword.exe", "excel.exe", "powerpnt.exe")
  | where InitiatingProcessCommandLine !contains "/dde"
  | where not(InitiatingProcessCommandLine has_any (".docx", "dotx",".xlsx", ".xltx", ".pptx")) // These files can't contain macros.
  // Enable the line below if the results are too noisy.
  //| where InitiatingProcessCommandLine has_any (".doc", ".wbk", ".docm", ".dot", ".dotm" ".xls", ".xlsm", ".xltm", ".xla",".xll", ".xlam", ".ppt", ".pptm", ".pot", ".potm", ".ppsm", ".sldm") 
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Sid
        columnName: InitiatingProcessAccountSid 
      - identifier: Name
        columnName: InitiatingProcessAccountName
      - identifier: NTDomain
        columnName: InitiatingProcessAccountDomain
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: DeviceName
  - entityType: Process
    fieldMappings:
      - identifier: CommandLine
        columnName: InitiatingProcessCommandLine
version: 1.0.1
kind: Scheduled

Stages and Predicates

Stage 1: `source`

DeviceEvents

Stage 2: `where`

| where ActionType in ("CreateRemoteThreadApiCall", "QueueUserApcRemoteApiCall", "SetThreadContextRemoteApiCall")

Stage 3: `where`

| where InitiatingProcessFileName in~ ("winword.exe", "excel.exe", "powerpnt.exe")

Stage 4: `where`

| where InitiatingProcessCommandLine !contains "/dde"

Stage 5: `where`

| where not(InitiatingProcessCommandLine has_any (".docx", "dotx",".xlsx", ".xltx", ".pptx"))

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

Field	Kind	Excluded values
`InitiatingProcessCommandLine`	contains	`/dde`
`InitiatingProcessCommandLine`	match	`.docx`, `dotx`, `.xlsx`, `.xltx`, `.pptx`

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
`ActionType`	in	`CreateRemoteThreadApiCall` transforms: `cased` `QueueUserApcRemoteApiCall` transforms: `cased` `SetThreadContextRemoteApiCall` transforms: `cased`
`InitiatingProcessFileName`	in	`excel.exe` corpus 8 (elastic 8) `powerpnt.exe` corpus 7 (elastic 7) `winword.exe` corpus 8 (elastic 8)

`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)

Suspicious Process Injection from Office application

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `where`

Stage 5: `where`

Exclusions

Indicators

Keyboard shortcuts

Search operators

Suspicious Process Injection from Office application

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Stage 1: source

Stage 2: where

Stage 3: where

Stage 4: where

Stage 5: where

Exclusions

Indicators

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `where`

Stage 5: `where`