Dev-0228 File Path Hashes November 2021

Severity: high
Time window: 6h
Author: Microsoft Security Research
Source: github.com/Azure/Azure-Sentinel

This hunting query looks for file paths/hashes related to observed activity by Dev-0228. The actor is known to use custom version of popular tool like PsExec, Procdump etc. to carry its activity. The risk score associated with each result is based on a number of factors, hosts with higher risk events should be investigated first.

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1569` System Services
Credential Access	`T1003` OS Credential Dumping

Event coverage

Provider	Event/ActionType	Title
Sysmon	Event ID 1	Process creation
Security-Auditing	Event ID 4688	A new process has been created.
Defender-DeviceProcessEvents	any	Process activity (any)

Rule body kusto

id: 3b443f22-9be9-4c35-ac70-a94757748439
name: Dev-0228 File Path Hashes November 2021
description: |
   'This hunting query looks for file paths/hashes related to observed activity by Dev-0228. The actor is known to use custom version of popular tool like PsExec, Procdump etc. to carry its activity.
    The risk score associated with each result is based on a number of factors, hosts with higher risk events should be investigated first.'
severity: High
requiredDataConnectors:
  - connectorId: MicrosoftDefenderAdvancedThreatProtection
    dataTypes:
      - SecurityAlert (MDATP)
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - DeviceProcessEvents
queryFrequency: 6h
queryPeriod: 6h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CredentialAccess
  - Execution
relevantTechniques:
  - T1569
  - T1003
query: | 
    let files1 = dynamic(["C:\\Windows\\TAPI\\lsa.exe", "C:\\Windows\\TAPI\\pa.exe", "C:\\Windows\\TAPI\\pc.exe", "C:\\Windows\\TAPI\\Rar.exe"]);
    let files2 = dynamic(["svchost.exe","wdmsvc.exe"]);
    let FileHash1 = dynamic(["43109fbe8b752f7a9076eaafa417d9ae5c6e827cd5374b866672263fdebd5ec3", "ab50d8d707b97712178a92bbac74ccc2a5699eb41c17aa77f713ff3e568dcedb", "010e32be0f86545e116a8bc3381a8428933eb8789f32c261c81fd5e7857d4a77",         "56cd102b9fc7f3523dad01d632525ff673259dbc9a091be0feff333c931574f7"]);
    let FileHash2 = dynamic(["2a1044e9e6e87a032f80c6d9ea6ae61bbbb053c0a21b186ecb3b812b49eb03b7", "9ab7e99ed84f94a7b6409b87e56dc6e1143b05034a5e4455e8c555dbbcd0d2dd", "18a072ccfab239e140d8f682e2874e8ff19d94311fc8bb9564043d3e0deda54b"]);
    DeviceProcessEvents
    | where ( FolderPath has_any (files1) and SHA256 has_any (FileHash1)) or (FolderPath has_any (files2) and SHA256 has_any (FileHash2))
    | extend DvcId = DeviceId
    | join kind=leftouter (SecurityAlert
    | where ProviderName =~ "MDATP"
    | extend ThreatName = tostring(parse_json(ExtendedProperties).ThreatName)
    | mv-expand todynamic(Entities)
    | extend DvcId = tostring(parse_json(Entities).MdatpDeviceId)
    | where isnotempty(DvcId)
    // Higher risk score are for Defender alerts related to threat actor
    | extend AlertRiskScore = iif(ThreatName has_any ("Backdoor:MSIL/ShellClient.A", "Backdoor:MSIL/ShellClient.A!dll", "Trojan:MSIL/Mimikatz.BA!MTB"), 1.0, 0.5)
    | project DvcId, AlertRiskScore) on DvcId
    | extend AlertRiskScore = iif(isempty(AlertRiskScore), 0.0, AlertRiskScore)
    | extend InitiatingProcessAccount = strcat(InitiatingProcessAccountDomain, "\\", InitiatingProcessAccountName)
    | extend HostName = tostring(split(DeviceName, ".")[0]), DomainIndex = toint(indexof(DeviceName, '.'))
    | extend HostNameDomain = iff(DomainIndex != -1, substring(DeviceName, DomainIndex + 1), DeviceName)
    | extend timestamp = TimeGenerated
entityMappings:
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: DeviceName
      - identifier: HostName
        columnName: HostName
      - identifier: NTDomain
        columnName: HostNameDomain
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: InitiatingProcessAccount
      - identifier: Name
        columnName: InitiatingProcessAccountName
      - identifier: NTDomain
        columnName: InitiatingProcessAccountDomain
  - entityType: File
    fieldMappings:
      - identifier: Name
        columnName: FileName
version: 1.1.2
kind: Scheduled
metadata:
    source:
        kind: Community
    author:
        name: Microsoft Security Research
    support:
        tier: Community
    categories:
        domains: [ "Security - 0-day Vulnerability" ]

Stages and Predicates

Parameters

let files1 = dynamic(["C:\\Windows\\TAPI\\lsa.exe", "C:\\Windows\\TAPI\\pa.exe", "C:\\Windows\\TAPI\\pc.exe", "C:\\Windows\\TAPI\\Rar.exe"]);
let files2 = dynamic(["svchost.exe","wdmsvc.exe"]);

Let binding: `FileHash1`

let FileHash1 = dynamic(["43109fbe8b752f7a9076eaafa417d9ae5c6e827cd5374b866672263fdebd5ec3", "ab50d8d707b97712178a92bbac74ccc2a5699eb41c17aa77f713ff3e568dcedb", "010e32be0f86545e116a8bc3381a8428933eb8789f32c261c81fd5e7857d4a77",         "56cd102b9fc7f3523dad01d632525ff673259dbc9a091be0feff333c931574f7"]);

Let binding: `FileHash2`

let FileHash2 = dynamic(["2a1044e9e6e87a032f80c6d9ea6ae61bbbb053c0a21b186ecb3b812b49eb03b7", "9ab7e99ed84f94a7b6409b87e56dc6e1143b05034a5e4455e8c555dbbcd0d2dd", "18a072ccfab239e140d8f682e2874e8ff19d94311fc8bb9564043d3e0deda54b"]);

Stage 1: `source`

DeviceProcessEvents

Stage 2: `where`

| where ( FolderPath has_any (files1) and SHA256 has_any (FileHash1)) or (FolderPath has_any (files2) and SHA256 has_any (FileHash2))

References FileHash1, FileHash2 (defined above).

Stage 3: `extend`

| extend DvcId = DeviceId

Stage 4: `join`

| join kind=leftouter (SecurityAlert
| where ProviderName =~ "MDATP"
| extend ThreatName = tostring(parse_json(ExtendedProperties).ThreatName)
| mv-expand todynamic(Entities)
| extend DvcId = tostring(parse_json(Entities).MdatpDeviceId)
| where isnotempty(DvcId)
| extend AlertRiskScore = iif(ThreatName has_any ("Backdoor:MSIL/ShellClient.A", "Backdoor:MSIL/ShellClient.A!dll", "Trojan:MSIL/Mimikatz.BA!MTB"), 1.0, 0.5)
| project DvcId, AlertRiskScore) on DvcId

Stage 5: `extend` (5 consecutive steps)

| extend AlertRiskScore = iif(isempty(AlertRiskScore), 0.0, AlertRiskScore)
| extend InitiatingProcessAccount = strcat(InitiatingProcessAccountDomain, "\\", InitiatingProcessAccountName)
| extend HostName = tostring(split(DeviceName, ".")[0]), DomainIndex = toint(indexof(DeviceName, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(DeviceName, DomainIndex + 1), DeviceName)
| extend timestamp = TimeGenerated

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
`DvcId`	is_not_null	(no value, null check)
`FolderPath`	match	`C:\\Windows\\TAPI\\Rar.exe` `C:\\Windows\\TAPI\\lsa.exe` `C:\\Windows\\TAPI\\pa.exe` `C:\\Windows\\TAPI\\pc.exe` `svchost.exe` `wdmsvc.exe`
`ProviderName`	eq	`MDATP` corpus 13 (kusto 13)
`SHA256`	match	`010e32be0f86545e116a8bc3381a8428933eb8789f32c261c81fd5e7857d4a77` `18a072ccfab239e140d8f682e2874e8ff19d94311fc8bb9564043d3e0deda54b` `2a1044e9e6e87a032f80c6d9ea6ae61bbbb053c0a21b186ecb3b812b49eb03b7` `43109fbe8b752f7a9076eaafa417d9ae5c6e827cd5374b866672263fdebd5ec3` `56cd102b9fc7f3523dad01d632525ff673259dbc9a091be0feff333c931574f7` `9ab7e99ed84f94a7b6409b87e56dc6e1143b05034a5e4455e8c555dbbcd0d2dd` `ab50d8d707b97712178a92bbac74ccc2a5699eb41c17aa77f713ff3e568dcedb`

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
`DvcId`	`extend`
`AlertRiskScore`	`extend`
`InitiatingProcessAccount`	`extend`
`DomainIndex`	`extend`
`HostName`	`extend`
`HostNameDomain`	`extend`
`timestamp`	`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)

Dev-0228 File Path Hashes November 2021

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Parameters

Let binding: `FileHash1`

Let binding: `FileHash2`

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `join`

Stage 5: `extend` (5 consecutive steps)

Indicators

Output fields

Keyboard shortcuts

Search operators

Dev-0228 File Path Hashes November 2021

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Parameters

Let binding: FileHash1

Let binding: FileHash2

Stage 1: source

Stage 2: where

Stage 3: extend

Stage 4: join

Stage 5: extend (5 consecutive steps)

Indicators

Output fields

Let binding: `FileHash1`

Let binding: `FileHash2`

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `join`

Stage 5: `extend` (5 consecutive steps)