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

queryPeriod: 5m
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."  
relevantTechniques:
- T1204
- T1566
- T1027
- T1486
- T1566.001
version: 1.0.1
customDetails:
  Sources: Sources
  Description: Description
  IndicatorID: IndicatorID
  ValidFrom: valid_from
  ThreatActors: ThreatActors
  Modified: modified
  Created: created
  SecurityVendors: SecurityVendors
  Country: Country
  Tags: Tags
  ConfidenceScore: ConfidenceScore
  TimeGenerated: TimeGenerated
  Roles: Roles
  RecommendedActions: RecommendedActions
  ThreatType: ThreatType
id: cd06dae8-7b79-436b-b1a6-9d256830f9dd
queryFrequency: 5m
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cyfirma Cyber Intelligence/Analytic Rules/FileHashIndicatorsBlockMediumSeverityRule.yaml
kind: Scheduled
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  
entityMappings:
- fieldMappings:
  - columnName: Algo_MD5
    identifier: Algorithm
  - columnName: MD5
    identifier: Value
  entityType: FileHash
- fieldMappings:
  - columnName: Algo_SHA1
    identifier: Algorithm
  - columnName: SHA1
    identifier: Value
  entityType: FileHash
- fieldMappings:
  - columnName: Algo_SHA256
    identifier: Algorithm
  - columnName: SHA256
    identifier: Value
  entityType: FileHash
eventGroupingSettings:
  aggregationKind: AlertPerResult
triggerOperator: GreaterThan
triggerThreshold: 0
suppressionEnabled: true
tactics:
- Execution
- InitialAccess
- DefenseEvasion
- Impact
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    enabled: false
    matchingMethod: AllEntities
    reopenClosedIncident: false
    lookbackDuration: PT5H
name: CYFIRMA - Medium severity File Hash Indicators with Block Action Rule
severity: Medium
requiredDataConnectors:
- connectorId: CyfirmaCyberIntelligenceDC
  dataTypes:
  - CyfirmaIndicators_CL
alertDetailsOverride:
  alertDescriptionFormat: '{{Description}} - {{name}} '
  alertDynamicProperties:
  - value: ProductName
    alertProperty: ProductName
  - value: ProviderName
    alertProperty: ProviderName
  alertDisplayNameFormat: 'High-Confidence File Hash Indicators with Block Action - {{name}} '
suppressionDuration: 5m
enabled: false

ARM