CYFIRMA - Medium severity File Hash Indicators with Block Action Rule

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Id	cd06dae8-7b79-436b-b1a6-9d256830f9dd
Rulename	CYFIRMA - Medium severity File Hash Indicators with Block Action Rule
Description	“This query retrieves file hash indicators marked for blocking, with no assigned role, from the CyfirmaIndicators_CL table. It extracts MD5, SHA1, and SHA256 hashes and includes threat metadata for use in preventive security controls such as EDRs, threat intel platforms, or automated blocklists.”
Severity	Medium
Tactics	Execution InitialAccess DefenseEvasion Impact
Techniques	T1204 T1566 T1027 T1486 T1566.001
Required data connectors	CyfirmaCyberIntelligenceDC
Kind	Scheduled
Query frequency	5m
Query period	5m
Trigger threshold	0
Trigger operator	GreaterThan
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cyfirma Cyber Intelligence/Analytic Rules/FileHashIndicatorsBlockMediumSeverityRule.yaml
Version	1.0.1
Arm template	cd06dae8-7b79-436b-b1a6-9d256830f9dd.json

KQL

// File Hash Indicators with Block Action
let timeFrame = 5m;
CyfirmaIndicators_CL 
| where  (ConfidenceScore < 80 and ConfidenceScore >= 50)
    and TimeGenerated between (ago(timeFrame) .. now())
    and pattern contains 'file:hashes' and RecommendedActions has 'Block' and (isempty(Roles) or not(Roles has_any ('Malware', 'Trojan')))
| extend MD5 = extract(@"file:hashes\.md5\s*=\s*'([a-fA-F0-9]{32})'", 1, pattern)
| extend SHA1 = extract(@"file:hashes\.'SHA-1'\s*=\s*'([a-fA-F0-9]{40})'", 1, pattern)
| extend SHA256 = extract(@"file:hashes\.'SHA-256'\s*=\s*'([a-fA-F0-9]{64})'", 1, pattern)
| extend
    Algo_MD5='MD5',
    Algo_SHA1= 'SHA1',
    Algo_SHA256='SHA256',
    ProviderName = 'CYFIRMA',
    ProductName = 'DeCYFIR/DeTCT'
| project  
    MD5,
    SHA1,
    SHA256,
    Algo_MD5,
    Algo_SHA1,
    Algo_SHA256,
    ThreatActors,
    Sources,
    RecommendedActions,
    Roles,
    Country,
    name,
    Description,
    ConfidenceScore,
    SecurityVendors,
    IndicatorID,
    created,
    modified,
    valid_from,
    Tags,
    ThreatType,
    TimeGenerated,
    ProductName,
    ProviderName

YAML

tactics:
- Execution
- InitialAccess
- DefenseEvasion
- Impact
id: cd06dae8-7b79-436b-b1a6-9d256830f9dd
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cyfirma Cyber Intelligence/Analytic Rules/FileHashIndicatorsBlockMediumSeverityRule.yaml
suppressionEnabled: true
alertDetailsOverride:
  alertDynamicProperties:
  - alertProperty: ProductName
    value: ProductName
  - alertProperty: ProviderName
    value: ProviderName
  alertDisplayNameFormat: 'High-Confidence File Hash Indicators with Block Action - {{name}} '
  alertDescriptionFormat: '{{Description}} - {{name}} '
description: |
  "This query retrieves file hash indicators marked for blocking, with no assigned role, from the CyfirmaIndicators_CL table. 
  It extracts MD5, SHA1, and SHA256 hashes and includes threat metadata for use in preventive security controls such as EDRs, threat intel platforms, or automated blocklists."  
version: 1.0.1
triggerThreshold: 0
entityMappings:
- fieldMappings:
  - identifier: Algorithm
    columnName: Algo_MD5
  - identifier: Value
    columnName: MD5
  entityType: FileHash
- fieldMappings:
  - identifier: Algorithm
    columnName: Algo_SHA1
  - identifier: Value
    columnName: SHA1
  entityType: FileHash
- fieldMappings:
  - identifier: Algorithm
    columnName: Algo_SHA256
  - identifier: Value
    columnName: SHA256
  entityType: FileHash
kind: Scheduled
incidentConfiguration:
  groupingConfiguration:
    reopenClosedIncident: false
    enabled: false
    matchingMethod: AllEntities
    lookbackDuration: PT5H
  createIncident: true
name: CYFIRMA - Medium severity File Hash Indicators with Block Action Rule
query: |
  // File Hash Indicators with Block Action
  let timeFrame = 5m;
  CyfirmaIndicators_CL 
  | where  (ConfidenceScore < 80 and ConfidenceScore >= 50)
      and TimeGenerated between (ago(timeFrame) .. now())
      and pattern contains 'file:hashes' and RecommendedActions has 'Block' and (isempty(Roles) or not(Roles has_any ('Malware', 'Trojan')))
  | extend MD5 = extract(@"file:hashes\.md5\s*=\s*'([a-fA-F0-9]{32})'", 1, pattern)
  | extend SHA1 = extract(@"file:hashes\.'SHA-1'\s*=\s*'([a-fA-F0-9]{40})'", 1, pattern)
  | extend SHA256 = extract(@"file:hashes\.'SHA-256'\s*=\s*'([a-fA-F0-9]{64})'", 1, pattern)
  | extend
      Algo_MD5='MD5',
      Algo_SHA1= 'SHA1',
      Algo_SHA256='SHA256',
      ProviderName = 'CYFIRMA',
      ProductName = 'DeCYFIR/DeTCT'
  | project  
      MD5,
      SHA1,
      SHA256,
      Algo_MD5,
      Algo_SHA1,
      Algo_SHA256,
      ThreatActors,
      Sources,
      RecommendedActions,
      Roles,
      Country,
      name,
      Description,
      ConfidenceScore,
      SecurityVendors,
      IndicatorID,
      created,
      modified,
      valid_from,
      Tags,
      ThreatType,
      TimeGenerated,
      ProductName,
      ProviderName  
suppressionDuration: 5m
queryPeriod: 5m
eventGroupingSettings:
  aggregationKind: AlertPerResult
severity: Medium
triggerOperator: GreaterThan
queryFrequency: 5m
customDetails:
  ThreatActors: ThreatActors
  Sources: Sources
  ValidFrom: valid_from
  Country: Country
  Roles: Roles
  Description: Description
  Tags: Tags
  ThreatType: ThreatType
  RecommendedActions: RecommendedActions
  ConfidenceScore: ConfidenceScore
  SecurityVendors: SecurityVendors
  Modified: modified
  IndicatorID: IndicatorID
  TimeGenerated: TimeGenerated
  Created: created
enabled: false
requiredDataConnectors:
- connectorId: CyfirmaCyberIntelligenceDC
  dataTypes:
  - CyfirmaIndicators_CL
relevantTechniques:
- T1204
- T1566
- T1027
- T1486
- T1566.001

ARM