Azure Excessive IP and VM Discovery

Severity: medium
Log types: Azure.MonitorActivity
Tags: AZT102, Discovery, Reconnaissance, Network Service Discovery, Remote System Discovery, Active Scanning, Vulnerability Scanning
Reference: https://microsoft.github.io/Azure-Threat-Research-Matrix/Reconnaissance/AZT101/AZT102/
Source: github.com/panther-labs/panther-analysis

Detects excessive read operations on Azure public IP addresses and virtual machines. Adversaries may enumerate public IPs and virtual machines to identify external attack surfaces, map network topology, and identify potential targets for exploitation. This reconnaissance pattern often precedes lateral movement attempts, privilege escalation, or targeted attacks. The threshold-based detection triggers when the same resource type is read excessively within a time window.

MITRE ATT&CK coverage

Tactic	Techniques
Reconnaissance	`T1595.002` Active Scanning: Vulnerability Scanning
Discovery	`T1018` Remote System Discovery, `T1046` Network Service Discovery

Rule body yaml

AnalysisType: rule
Filename: azure_network_ip_discovery.py
RuleID: "Azure.MonitorActivity.Network.IPDiscovery"
DisplayName: "Azure Excessive IP and VM Discovery"
Enabled: true
LogTypes:
  - Azure.MonitorActivity
Severity: Medium
Threshold: 50
Description: >
  Detects excessive read operations on Azure public IP addresses and virtual machines. Adversaries
  may enumerate public IPs and virtual machines to identify external attack surfaces, map network
  topology, and identify potential targets for exploitation. This reconnaissance pattern often
  precedes lateral movement attempts, privilege escalation, or targeted attacks. The threshold-based
  detection triggers when the same resource type is read excessively within a time window.
Reports:
  MITRE ATT&CK:
    - TA0007:T1046 # Discovery: Network Service Discovery
    - TA0007:T1018 # Discovery: Remote System Discovery
    - TA0043:T1595.002 # Reconnaissance: Active Scanning - Vulnerability Scanning
Tags:
  - AZT102
  - Discovery
  - Reconnaissance
  - Network Service Discovery
  - Remote System Discovery
  - Active Scanning
  - Vulnerability Scanning
Runbook: |
  1. Query Azure Monitor Activity logs for all public IP address and virtual machine read operations by the callerIpAddress in the 24 hours before and after the alert to identify the scope of reconnaissance activity
  2. Find all resource read operations (network security groups, route tables, virtual networks, storage accounts) by the same callerIpAddress in the 6 hours before and after the alert to determine if this is part of broader reconnaissance
  3. Check if the callerIpAddress has performed similar high-volume read operations in the past 90 days to establish if this is normal administrative activity or anomalous behavior
Reference: https://microsoft.github.io/Azure-Threat-Research-Matrix/Reconnaissance/AZT101/AZT102/
SummaryAttributes:
  - resourceId
  - location
  - callerIpAddress
  - correlationId
Tests:
  - Name: Public IP Address Read Success
    ExpectedResult: true
    Log:
      {
        "time": "2025-12-22T10:30:00.0000000Z",
        "resourceId": "/subscriptions/12345678-1234-1234-1234-123456789abc/resourceGroups/network-rg/providers/Microsoft.Network/publicIPAddresses/myPublicIP",
        "operationName": "MICROSOFT.NETWORK/PUBLICIPADDRESSES/READ",
        "operationVersion": "2021-05-01",
        "category": "Administrative",
        "resultType": "Success",
        "resultSignature": "200",
        "callerIpAddress": "1.1.1.1",
        "correlationId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
        "level": "Informational",
        "location": "eastus",
        "tenantId": "87654321-4321-4321-4321-111111111111"
      }
  - Name: Virtual Machine Read Success
    ExpectedResult: true
    Log:
      {
        "time": "2025-12-22T11:00:00.0000000Z",
        "resourceId": "/subscriptions/11111111-1111-1111-1111-111111111111/resourceGroups/compute-rg/providers/Microsoft.Compute/virtualMachines/myVM",
        "operationName": "MICROSOFT.COMPUTE/VIRTUALMACHINES/READ",
        "operationVersion": "2021-07-01",
        "category": "Administrative",
        "resultType": "Success",
        "resultSignature": "200",
        "callerIpAddress": "2.2.2.2",
        "correlationId": "b2c3d4e5-f6a7-8901-bcde-f23456789012",
        "level": "Informational",
        "location": "westeurope",
        "tenantId": "22222222-2222-2222-2222-222222222222"
      }
  - Name: Public IP Address Read Case Insensitive
    ExpectedResult: true
    Log:
      {
        "time": "2025-12-22T11:15:00.0000000Z",
        "resourceId": "/subscriptions/33333333-3333-3333-3333-333333333333/resourceGroups/network-rg/providers/Microsoft.Network/publicIPAddresses/pip-prod",
        "operationName": "microsoft.network/publicipaddresses/read",
        "category": "Administrative",
        "resultType": "Succeeded",
        "callerIpAddress": "3.3.3.3",
        "correlationId": "c3d4e5f6-a7b8-9012-cdef-333333333333",
        "level": "Information",
        "location": "centralus",
        "tenantId": "33333333-3333-3333-3333-333333333333"
      }
  - Name: Virtual Machine Read Case Insensitive
    ExpectedResult: true
    Log:
      {
        "time": "2025-12-22T11:30:00.0000000Z",
        "resourceId": "/subscriptions/44444444-4444-4444-4444-444444444444/resourceGroups/compute-rg/providers/Microsoft.Compute/virtualMachines/vm-prod-001",
        "operationName": "microsoft.compute/virtualmachines/read",
        "category": "Administrative",
        "resultType": "Succeeded",
        "callerIpAddress": "4.4.4.4",
        "correlationId": "d4e5f6a7-b8c9-0123-def0-444444444444",
        "level": "Information",
        "location": "westus",
        "tenantId": "44444444-4444-4444-4444-444444444444"
      }
  - Name: Different Operation
    ExpectedResult: false
    Log:
      {
        "time": "2025-12-22T14:00:00.0000000Z",
        "resourceId": "/subscriptions/88888888-8888-8888-8888-888888888888/resourceGroups/storage-rg/providers/Microsoft.Storage/storageAccounts/mystorageaccount",
        "operationName": "MICROSOFT.STORAGE/STORAGEACCOUNTS/READ",
        "category": "Administrative",
        "resultType": "Success",
        "callerIpAddress": "8.8.8.8",
        "correlationId": "b8c9d0e1-f2a3-4567-1234-888888888888",
        "tenantId": "88888888-8888-8888-8888-888888888888"
      }

Detection logic

Condition

operationName in ["MICROSOFT.NETWORK/PUBLICIPADDRESSES/READ", "MICROSOFT.COMPUTE/VIRTUALMACHINES/READ"]
resultType in ["Success", "Succeeded"]

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
`operationName`	in	`MICROSOFT.COMPUTE/VIRTUALMACHINES/READ` `MICROSOFT.NETWORK/PUBLICIPADDRESSES/READ`
`resultType`	in	`Succeeded` `Success`

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
`resourceId`

`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)