Chia_Crypto_Mining IOC - June 2021

Status: available
Severity: low
Time window: 6h
Source: github.com/Azure/Azure-Sentinel

Identifies a match across IOC's related to Chia cryptocurrency farming/plotting activity

MITRE ATT&CK coverage

Tactic	Techniques
Impact	`T1496` Resource Hijacking

Event coverage

Provider	Event	Title
Security-Auditing	Event ID 4688	A new process has been created.

Rule body kusto

id: 4d173248-439b-4741-8b37-f63ad0c896ae
name: Chia_Crypto_Mining IOC - June 2021
description: | 
  'Identifies a match across IOC's related to Chia cryptocurrency farming/plotting activity'
severity: Low
status: Available 
requiredDataConnectors: 
  - connectorId: WindowsForwardedEvents
    dataTypes: 
      - WindowsEvent 
queryFrequency: 6h 
queryPeriod: 6h 
triggerOperator: gt 
triggerThreshold: 0 
tactics: 
  - Impact
relevantTechniques:
  - T1496
tags:
  - Chia 
  - ParentAlert: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/MultipleDataSources/ChiaCryptoMining.yaml
    version: 1.1.0
query:  |  
  let iocs = externaldata(DateAdded:string,IoC:string,Type:string,TLP:string) [@"https://raw.githubusercontent.com/Azure/Azure-Sentinel/master/Sample%20Data/Feeds/ChiaCryptoIOC.csv"] with (format="csv", ignoreFirstRecord=True);
  let process = (iocs | where Type =~ "process" | project IoC);
  //This query uses sysmon data, sections that have - | where Source == "Microsoft-Windows-Sysmon" - may need to be updated with latest
  WindowsEvent
  | where EventID == '4688' and EventData has_any (process)
  | extend NewProcessName = tostring(EventData.NewProcessName)
  | where NewProcessName  has_any (process)
  | extend ParentProcessName = tostring(EventData.ParentProcessName)
    , Account =  strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
    , NewProcessId = tostring(EventData.NewProcessId)
  | extend Computer, Account, File = tostring(split(NewProcessName, '\\', -1)[-1]), AlertDetail = 'Chia crypto IOC detected'
  | extend FilePath = replace_string(NewProcessName, File, '')
  | project TimeGenerated, File, AlertDetail, FilePath,Computer, NewProcessName, ParentProcessName, Account, NewProcessId, Type
  | extend AccountName = tostring(split(Account, @'\')[1]), AccountNTDomain = tostring(split(Account, @'\')[0])
  | extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: Account
      - identifier: Name
        columnName: AccountName
      - identifier: NTDomain
        columnName: AccountNTDomain
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: Computer
      - identifier: HostName
        columnName: HostName
      - identifier: DnsDomain
        columnName: HostNameDomain
  - entityType: File
    fieldMappings:
      - identifier: Name
        columnName: File
      - identifier: Directory
        columnName: FilePath
version: 1.0.4
kind: Scheduled

Stages and Predicates

Let binding: `iocs`

let iocs = externaldata(DateAdded:string,IoC:string,Type:string,TLP:string) [@"https://raw.githubusercontent.com/Azure/Azure-Sentinel/master/Sample%20Data/Feeds/ChiaCryptoIOC.csv"] with (format="csv", ignoreFirstRecord=True);

Let binding: `process`

let process = (iocs | where Type =~ "process" | project IoC);

Derived from iocs.

Stage 1: `source`

WindowsEvent

Stage 2: `where`

| where EventID == '4688' and EventData has_any (process)

References process (defined above).

Stage 3: `extend`

| extend NewProcessName = tostring(EventData.NewProcessName)

Stage 4: `where`

| where NewProcessName  has_any (process)

References process (defined above).

Stage 5: `extend` (3 consecutive steps)

| extend ParentProcessName = tostring(EventData.ParentProcessName)
  , Account =  strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
  , NewProcessId = tostring(EventData.NewProcessId)
| extend Computer, Account, File = tostring(split(NewProcessName, '\\', -1)[-1]), AlertDetail = 'Chia crypto IOC detected'
| extend FilePath = replace_string(NewProcessName, File, '')

Stage 6: `project`

| project TimeGenerated, File, AlertDetail, FilePath,Computer, NewProcessName, ParentProcessName, Account, NewProcessId, Type

Stage 7: `extend` (3 consecutive steps)

| extend AccountName = tostring(split(Account, @'\')[1]), AccountNTDomain = tostring(split(Account, @'\')[0])
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)

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
`EventData`	match	`process`
`EventID`	eq	`4688` transforms: `cased` corpus 313 (splunk 283, kusto 30)
`NewProcessName`	match	`process`

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
`Account`	`project`
`AlertDetail`	`project`
`Computer`	`project`
`File`	`project`
`FilePath`	`project`
`NewProcessId`	`project`
`NewProcessName`	`project`
`ParentProcessName`	`project`
`TimeGenerated`	`project`
`Type`	`project`
`AccountNTDomain`	`extend`
`AccountName`	`extend`
`DomainIndex`	`extend`
`HostName`	`extend`
`HostNameDomain`	`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)

Chia_Crypto_Mining IOC - June 2021

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Let binding: `iocs`

Let binding: `process`

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `where`

Stage 5: `extend` (3 consecutive steps)

Stage 6: `project`

Stage 7: `extend` (3 consecutive steps)

Indicators

Output fields

Keyboard shortcuts

Search operators

Chia_Crypto_Mining IOC - June 2021

MITRE ATT&CK coverage

Event coverage

Rule body kusto

Stages and Predicates

Let binding: iocs

Let binding: process

Stage 1: source

Stage 2: where

Stage 3: extend

Stage 4: where

Stage 5: extend (3 consecutive steps)

Stage 6: project

Stage 7: extend (3 consecutive steps)

Indicators

Output fields

Let binding: `iocs`

Let binding: `process`

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `where`

Stage 5: `extend` (3 consecutive steps)

Stage 6: `project`

Stage 7: `extend` (3 consecutive steps)