GCP Security Command Center - Detect Firewall rules allowing unrestricted high-risk ports

Status: available
Severity: high
Time window: 1h
Group by: Description, ExternalUri, FindingName, FirewallName, ProjectName, ResourceName, Severity
Source: github.com/Azure/Azure-Sentinel

This query detects GCP Firewall rules that allow unrestricted (0.0.0.0/0) ingress to high-risk ports using Google Cloud Security Command Center OPEN_FIREWALL findings. Publicly exposed management, database, and service ports (e.g., RDP 3389, SSH 22, SQL 1433/3306) significantly increase the risk of brute-force attacks, exploitation, and lateral movement.

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1133` External Remote Services
Discovery	`T1046` Network Service Discovery
Lateral Movement	`T1021` Remote Services

Rule body kusto

id: f4f92ca4-6ebe-4f2a-90e5-b0d04b709651
name: GCP Security Command Center - Detect Firewall rules allowing unrestricted high-risk ports
description: |
  This query detects GCP Firewall rules that allow unrestricted (0.0.0.0/0) ingress to high-risk ports using Google Cloud Security Command Center OPEN_FIREWALL findings.
  Publicly exposed management, database, and service ports (e.g., RDP 3389, SSH 22, SQL 1433/3306) significantly increase the risk of brute-force attacks, exploitation, and lateral movement.
severity: High
status: Available
requiredDataConnectors:
  - connectorId: GoogleSCCDefinition
    dataTypes:
      - GoogleCloudSCC
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
  - LateralMovement
  - Discovery
relevantTechniques:
  - T1133
  - T1021
  - T1046
tags:
  - PCI-DSS v3.2.1 1.2.1
query: |
  let HighRiskPorts = dynamic([3389,20,23,110,143,3306,8080,1433,9200,9300,25,445,135,21,1434,4333,5432,5500,5601,22,3000,5000,8088,8888]);
  GoogleCloudSCC
  | where tostring(Findings.state) == "ACTIVE"
  | extend FindingCategory = tostring(Findings.category)
  | where FindingCategory == "OPEN_FIREWALL"
  | extend FindingsJson = parse_json(Findings)
  | extend SourcePropertiesJson = parse_json(tostring(FindingsJson.sourceProperties))
  | extend IpRulesJson = parse_json(tostring(FindingsJson.ipRules))
  | where tostring(FindingsJson.state) == "ACTIVE"
  | where tostring(SourcePropertiesJson.ExternalSourceRanges) contains "0.0.0.0/0"
  | extend AllowedIpRules = parse_json(tostring(IpRulesJson.allowed.ipRules))
  | mv-expand IpRule = AllowedIpRules
  | extend PortRanges = parse_json(tostring(IpRule.portRanges))
  | mv-expand PortRange = PortRanges
  | extend MinPort = toint(PortRange.min), MaxPort = toint(PortRange.max)
  | where MinPort in (HighRiskPorts) or MaxPort in (HighRiskPorts)
  | extend 
      ResourceName = tostring(FindingsJson.resourceName),
      FindingName = tostring(FindingsJson.name),
      Protocol = tostring(IpRule.protocol),
      Severity = tostring(FindingsJson.severity),
      Description = tostring(FindingsJson.description),
      ExternalUri = tostring(FindingsJson.externalUri),
      AttackExposureScore = todouble(FindingsJson.attackExposure.score),
      ProjectName = extract(@"projects/([^/]+)", 1, tostring(FindingsJson.resourceName)),
      FirewallName = extract(@"firewalls/([^/]+)", 1, tostring(FindingsJson.resourceName))
  | extend PortInfo = case(
      MinPort == MaxPort, tostring(MinPort),
      strcat(tostring(MinPort), "-", tostring(MaxPort))
  )
  | summarize 
      TimeGenerated = max(TimeGenerated), 
      OpenHighRiskPorts = make_set(PortInfo),
      Protocols = make_set(Protocol),
      AttackExposureScore = max(AttackExposureScore)
      by ProjectName, FirewallName, ResourceName, FindingName, Severity, Description, ExternalUri
  | extend OpenHighRiskPorts = strcat_array(OpenHighRiskPorts, ", ")
  | extend Protocols = strcat_array(Protocols, ", ")
entityMappings:
  - entityType: CloudApplication
    fieldMappings:
      - identifier: Name
        columnName: ResourceName
customDetails:
  ProjectName: ProjectName
  FirewallName: FirewallName
  FindingId: FindingName
  OpenHighRiskPorts: OpenHighRiskPorts
  Protocols: Protocols
  AttackExposureScore: AttackExposureScore
  ExternalUri: ExternalUri
alertDetailsOverride:
  alertDisplayNameFormat: "GCP Firewall {{FirewallName}} allows unrestricted high-risk ports"
  alertDescriptionFormat: |-
    GCP Firewall {{FirewallName}} in project {{ProjectName}} allows unrestricted (0.0.0.0/0) ingress to high-risk ports: {{OpenHighRiskPorts}}.
version: 1.0.0
kind: Scheduled

Stages and Predicates

Parameters

let HighRiskPorts = dynamic([3389,20,23,110,143,3306,8080,1433,9200,9300,25,445,135,21,1434,4333,5432,5500,5601,22,3000,5000,8088,8888]);

Stage 1: `source`

GoogleCloudSCC

Stage 2: `where`

| where tostring(Findings.state) == "ACTIVE"

Stage 3: `extend`

| extend FindingCategory = tostring(Findings.category)

Stage 4: `where`

| where FindingCategory == "OPEN_FIREWALL"

Stage 5: `extend` (3 consecutive steps)

| extend FindingsJson = parse_json(Findings)
| extend SourcePropertiesJson = parse_json(tostring(FindingsJson.sourceProperties))
| extend IpRulesJson = parse_json(tostring(FindingsJson.ipRules))

Stage 6: `where`

| where tostring(FindingsJson.state) == "ACTIVE"

Stage 7: `where`

| where tostring(SourcePropertiesJson.ExternalSourceRanges) contains "0.0.0.0/0"

Stage 8: `extend`

| extend AllowedIpRules = parse_json(tostring(IpRulesJson.allowed.ipRules))

Stage 9: `mv-expand`

| mv-expand IpRule = AllowedIpRules

Stage 10: `extend`

| extend PortRanges = parse_json(tostring(IpRule.portRanges))

Stage 11: `mv-expand`

| mv-expand PortRange = PortRanges

Stage 12: `extend`

| extend MinPort = toint(PortRange.min), MaxPort = toint(PortRange.max)

Stage 13: `where`

| where MinPort in (HighRiskPorts) or MaxPort in (HighRiskPorts)

Stage 14: `extend`

| extend 
    ResourceName = tostring(FindingsJson.resourceName),
    FindingName = tostring(FindingsJson.name),
    Protocol = tostring(IpRule.protocol),
    Severity = tostring(FindingsJson.severity),
    Description = tostring(FindingsJson.description),
    ExternalUri = tostring(FindingsJson.externalUri),
    AttackExposureScore = todouble(FindingsJson.attackExposure.score),
    ProjectName = extract(@"projects/([^/]+)", 1, tostring(FindingsJson.resourceName)),
    FirewallName = extract(@"firewalls/([^/]+)", 1, tostring(FindingsJson.resourceName))

Stage 15: `extend`

| extend PortInfo = case(
    MinPort == MaxPort, tostring(MinPort),
    strcat(tostring(MinPort), "-", tostring(MaxPort))
)

PortInfo =

ifMinPort == "MaxPort"tostring(MinPort)

elsestrcat(tostring(MinPort), "-", tostring(MaxPort))

Stage 16: `summarize`

| summarize 
    TimeGenerated = max(TimeGenerated), 
    OpenHighRiskPorts = make_set(PortInfo),
    Protocols = make_set(Protocol),
    AttackExposureScore = max(AttackExposureScore)
    by ProjectName, FirewallName, ResourceName, FindingName, Severity, Description, ExternalUri

Stage 17: `extend`

| extend OpenHighRiskPorts = strcat_array(OpenHighRiskPorts, ", ")

Stage 18: `extend`

| extend Protocols = strcat_array(Protocols, ", ")

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
`ExternalSourceRanges`	contains	`0.0.0.0/0` transforms: `tostring`
`FindingCategory`	eq	`OPEN_FIREWALL` transforms: `cased`
`MaxPort`	in	`110` transforms: `cased` `135` transforms: `cased` `143` transforms: `cased` `1433` transforms: `cased` `1434` transforms: `cased` `20` transforms: `cased` `21` transforms: `cased` `22` transforms: `cased` `23` transforms: `cased` `25` transforms: `cased` `3000` transforms: `cased` `3306` transforms: `cased` `3389` transforms: `cased` `4333` transforms: `cased` `445` transforms: `cased` `5000` transforms: `cased` `5432` transforms: `cased` `5500` transforms: `cased` `5601` transforms: `cased` `8080` transforms: `cased` `8088` transforms: `cased` `8888` transforms: `cased` `9200` transforms: `cased` `9300` transforms: `cased`
`MinPort`	in	`110` transforms: `cased` `135` transforms: `cased` `143` transforms: `cased` `1433` transforms: `cased` `1434` transforms: `cased` `20` transforms: `cased` `21` transforms: `cased` `22` transforms: `cased` `23` transforms: `cased` `25` transforms: `cased` `3000` transforms: `cased` `3306` transforms: `cased` `3389` transforms: `cased` `4333` transforms: `cased` `445` transforms: `cased` `5000` transforms: `cased` `5432` transforms: `cased` `5500` transforms: `cased` `5601` transforms: `cased` `8080` transforms: `cased` `8088` transforms: `cased` `8888` transforms: `cased` `9200` transforms: `cased` `9300` transforms: `cased`
`state`	eq	`ACTIVE` transforms: `tostring`, `cased`

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
`AttackExposureScore`	`summarize`
`Description`	`summarize`
`ExternalUri`	`summarize`
`FindingName`	`summarize`
`FirewallName`	`summarize`
`OpenHighRiskPorts`	`extend`
`ProjectName`	`summarize`
`Protocols`	`extend`
`ResourceName`	`summarize`
`Severity`	`summarize`
`TimeGenerated`	`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)

GCP Security Command Center - Detect Firewall rules allowing unrestricted high-risk ports

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Parameters

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `where`

Stage 5: `extend` (3 consecutive steps)

Stage 6: `where`

Stage 7: `where`

Stage 8: `extend`

Stage 9: `mv-expand`

Stage 10: `extend`

Stage 11: `mv-expand`

Stage 12: `extend`

Stage 13: `where`

Stage 14: `extend`

Stage 15: `extend`

Stage 16: `summarize`

Stage 17: `extend`

Stage 18: `extend`

Indicators

Output fields

Keyboard shortcuts

Search operators

GCP Security Command Center - Detect Firewall rules allowing unrestricted high-risk ports

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Parameters

Stage 1: source

Stage 2: where

Stage 3: extend

Stage 4: where

Stage 5: extend (3 consecutive steps)

Stage 6: where

Stage 7: where

Stage 8: extend

Stage 9: mv-expand

Stage 10: extend

Stage 11: mv-expand

Stage 12: extend

Stage 13: where

Stage 14: extend

Stage 15: extend

Stage 16: summarize

Stage 17: extend

Stage 18: extend

Indicators

Output fields

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `where`

Stage 5: `extend` (3 consecutive steps)

Stage 6: `where`

Stage 7: `where`

Stage 8: `extend`

Stage 9: `mv-expand`

Stage 10: `extend`

Stage 11: `mv-expand`

Stage 12: `extend`

Stage 13: `where`

Stage 14: `extend`

Stage 15: `extend`

Stage 16: `summarize`

Stage 17: `extend`

Stage 18: `extend`