Multiple Sources Affected by the Same TI Destination

Status: available
Severity: medium
Time window: 1d
Group by: Fqdn, ThreatDescription
Source: github.com/Azure/Azure-Sentinel

'Identifies multiple machines trying to reach out to the same destination blocked by TI in Azure Firewall. This can indicate attack on the organization by the same attack group. Configurable Parameters: - Minimum affected threshold - alert only if more than this number of hosts affected. Default is set to 5. - Recommendation is to use the new resource specific logs. If you are using both, the TiTraffic Count will be duplicated.'

MITRE ATT&CK coverage

Tactic	Techniques
Command & Control	`T1071` Application Layer Protocol
Exfiltration	`T1041` Exfiltration Over C2 Channel

Rule body kusto

id: 4644baf7-3464-45dd-bd9d-e07687e25f81
name: Multiple Sources Affected by the Same TI Destination
description: |
  'Identifies multiple machines trying to reach out to the same destination blocked by TI in Azure Firewall. This can indicate attack on the organization by the same attack group.
  
  Configurable Parameters:
  
  - Minimum affected threshold - alert only if more than this number of hosts affected. Default is set to 5.
  - Recommendation is to use the new resource specific logs. If you are using both, the TiTraffic Count will be duplicated.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: AzureFirewall
    dataTypes: 
      - AzureDiagnostics
      - AZFWThreatIntel
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Exfiltration
  - CommandAndControl
relevantTechniques:
  - T1041
  - T1071
query: |
  let Timeframe = 1d;
  let StartTime = ago(Timeframe);
  let EndTime = now(); 
  let MinAffectedThreshold = 5;
  union isfuzzy=true
  (AzureDiagnostics 
  | where TimeGenerated  between (StartTime .. EndTime)
  | where OperationName == "AzureFirewallThreatIntelLog"
  | parse msg_s with * "from " SourceIp ":" SourcePort:int " to " Fqdn ":" DestinationPort:int  "." * "Action: Deny. " ThreatDescription),
  (AZFWThreatIntel
  | where TimeGenerated between (StartTime .. EndTime))
  | extend Fqdn = DestinationIp
  | summarize TiTrafficCount = count(), dCountSourceIps = dcount(SourceIp), AffectedIps = make_set(SourceIp, 10000) by Fqdn, ThreatDescription
  | where array_length(AffectedIps) > MinAffectedThreshold
  | mv-expand SourceIp = AffectedIps
  | order by TiTrafficCount desc, Fqdn asc, parse_ipv4(tostring(SourceIp)) asc
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: SourceIp
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: Fqdn
customDetails:
  ThreatDescription: ThreatDescription
version: 1.1.5
kind: Scheduled

Stages and Predicates

Parameters

let Timeframe = 1d;
let StartTime = ago(Timeframe);
let EndTime = now();
let MinAffectedThreshold = 5;

union `isfuzzy=true` (2 sources)

Each leg below queries one source; the rule matches if any leg does. Sources: AzureDiagnostics, AZFWThreatIntel

Leg 1: `AzureDiagnostics`

AzureDiagnostics 
| where TimeGenerated  between (StartTime .. EndTime)
| where OperationName == "AzureFirewallThreatIntelLog"
| parse msg_s with * "from " SourceIp ":" SourcePort:int " to " Fqdn ":" DestinationPort:int  "." * "Action: Deny. " ThreatDescription

Leg 2: `AZFWThreatIntel`

AZFWThreatIntel
| where TimeGenerated between (StartTime .. EndTime)

Applied to the combined result

| extend Fqdn = DestinationIp
| summarize TiTrafficCount = count(), dCountSourceIps = dcount(SourceIp), AffectedIps = make_set(SourceIp, 10000) by Fqdn, ThreatDescription
| where array_length(AffectedIps) > MinAffectedThreshold
| mv-expand SourceIp = AffectedIps
| order by TiTrafficCount desc, Fqdn asc, parse_ipv4(tostring(SourceIp)) asc

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
`AffectedIps`	gt	`5` transforms: `array_length`
`OperationName`	eq	`AzureFirewallThreatIntelLog` transforms: `cased`
`TimeGenerated`	ge	`StartTime`
`TimeGenerated`	le	`EndTime`

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
`AffectedIps`	`summarize`
`Fqdn`	`summarize`
`ThreatDescription`	`summarize`
`TiTrafficCount`	`summarize`
`dCountSourceIps`	`summarize`

`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)

Multiple Sources Affected by the Same TI Destination

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Parameters

union `isfuzzy=true` (2 sources)

Leg 1: `AzureDiagnostics`

Leg 2: `AZFWThreatIntel`

Applied to the combined result

Indicators

Output fields

Keyboard shortcuts

Search operators

Multiple Sources Affected by the Same TI Destination

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Parameters

union isfuzzy=true (2 sources)

Leg 1: AzureDiagnostics

Leg 2: AZFWThreatIntel

Applied to the combined result

Indicators

Output fields

union `isfuzzy=true` (2 sources)

Leg 1: `AzureDiagnostics`

Leg 2: `AZFWThreatIntel`