Netskope - Anomalous User Behavior (High Volume from Unmanaged Device)

Status: available
Severity: medium
Time window: 1h
Group by: CsUsername, XCDevice, XCsAccessMethod
Source: github.com/Azure/Azure-Sentinel

Detects anomalous user behavior including high data volume transfers from unmanaged devices, unusual access patterns, and suspicious application usage.

MITRE ATT&CK coverage

Tactic	Techniques
Collection	`T1074` Data Staged
Exfiltration	`T1567` Exfiltration Over Web Service

Rule body kusto

id: fa4c4f1c-3c5f-4c3a-a13f-924c30db56e9
name: Netskope - Anomalous User Behavior (High Volume from Unmanaged Device)
description: |
  Detects anomalous user behavior including high data volume transfers from unmanaged devices, unusual access patterns, and suspicious application usage.
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: NetskopeWebTxConnector
    dataTypes:
      - NetskopeWebTransactions_CL
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Exfiltration
  - Collection
relevantTechniques:
  - T1567
  - T1074
query: |
  let highVolumeThresholdGB = 1;
  NetskopeWebTransactions_CL
  | where TimeGenerated > ago(1h)
  | where isnotempty(CsUsername)
  | summarize 
      TotalBytes = sum(Bytes),
      UploadBytes = sum(CsBytes),
      DownloadBytes = sum(ScBytes),
      UniqueApps = dcount(XCsApp),
      Apps = make_set(XCsApp, 20),
      UniqueHosts = dcount(CsHost),
      Activities = make_set(XCsAppActivity),
      Countries = make_set(XCCountry),
      Devices = make_set(XCDevice),
      AccessMethods = make_set(XCsAccessMethod),
      EventCount = count()
      by CsUsername, XCDevice, XCsAccessMethod
  | extend 
      TotalGB = round(TotalBytes / 1073741824.0, 3),
      UploadGB = round(UploadBytes / 1073741824.0, 3),
      DownloadGB = round(DownloadBytes / 1073741824.0, 3)
  | where TotalGB > highVolumeThresholdGB
  | extend IsUnmanagedDevice = XCDevice =~ 'unmanaged' or XCDevice =~ 'BYOD' or XCDevice =~ 'Personal' or XCDevice =~ 'Unknown' or XCsAccessMethod != 'Client'
  | where IsUnmanagedDevice or TotalGB > 5 or UniqueApps > 20
  | extend RiskIndicators = strcat_array(array_concat(
      iff(IsUnmanagedDevice, dynamic(['Unmanaged Device']), dynamic([])),
      iff(TotalGB > 5, dynamic(['High Data Volume']), dynamic([])),
      iff(UniqueApps > 20, dynamic(['Many Apps Accessed']), dynamic([])),
      iff(array_length(Countries) > 1, dynamic(['Multiple Countries']), dynamic([]))
  ), ', ')
  | project 
      TimeGenerated = now(),
      User = CsUsername,
      Device = XCDevice,
      AccessMethod = XCsAccessMethod,
      TotalDataGB = TotalGB,
      UploadGB,
      DownloadGB,
      UniqueApplications = UniqueApps,
      Applications = Apps,
      UniqueHosts,
      Activities,
      Countries,
      EventCount,
      IsUnmanagedDevice,
      RiskIndicators
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: User
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: Device
version: 1.0.0
kind: Scheduled

Stages and Predicates

Parameters

let highVolumeThresholdGB = 1;

Stage 1: `source`

NetskopeWebTransactions_CL

Stage 2: `where`

| where TimeGenerated > ago(1h)

Stage 3: `where`

| where isnotempty(CsUsername)

Stage 4: `summarize`

| summarize 
    TotalBytes = sum(Bytes),
    UploadBytes = sum(CsBytes),
    DownloadBytes = sum(ScBytes),
    UniqueApps = dcount(XCsApp),
    Apps = make_set(XCsApp, 20),
    UniqueHosts = dcount(CsHost),
    Activities = make_set(XCsAppActivity),
    Countries = make_set(XCCountry),
    Devices = make_set(XCDevice),
    AccessMethods = make_set(XCsAccessMethod),
    EventCount = count()
    by CsUsername, XCDevice, XCsAccessMethod

Stage 5: `extend`

| extend 
    TotalGB = round(TotalBytes / 1073741824.0, 3),
    UploadGB = round(UploadBytes / 1073741824.0, 3),
    DownloadGB = round(DownloadBytes / 1073741824.0, 3)

Stage 6: `where`

| where TotalGB > highVolumeThresholdGB

Stage 7: `extend`

| extend IsUnmanagedDevice = XCDevice =~ 'unmanaged' or XCDevice =~ 'BYOD' or XCDevice =~ 'Personal' or XCDevice =~ 'Unknown' or XCsAccessMethod != 'Client'

Stage 8: `where`

| where IsUnmanagedDevice or TotalGB > 5 or UniqueApps > 20

Stage 9: `extend`

| extend RiskIndicators = strcat_array(array_concat(
    iff(IsUnmanagedDevice, dynamic(['Unmanaged Device']), dynamic([])),
    iff(TotalGB > 5, dynamic(['High Data Volume']), dynamic([])),
    iff(UniqueApps > 20, dynamic(['Many Apps Accessed']), dynamic([])),
    iff(array_length(Countries) > 1, dynamic(['Multiple Countries']), dynamic([]))
), ', ')

Stage 10: `project`

| project 
    TimeGenerated = now(),
    User = CsUsername,
    Device = XCDevice,
    AccessMethod = XCsAccessMethod,
    TotalDataGB = TotalGB,
    UploadGB,
    DownloadGB,
    UniqueApplications = UniqueApps,
    Applications = Apps,
    UniqueHosts,
    Activities,
    Countries,
    EventCount,
    IsUnmanagedDevice,
    RiskIndicators

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
`CsUsername`	is_not_null	(no value, null check)
`TotalGB`	gt	`1` transforms: `cased` `5` transforms: `cased`
`UniqueApps`	gt	`20` transforms: `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
`AccessMethod`	`project`
`Activities`	`project`
`Applications`	`project`
`Countries`	`project`
`Device`	`project`
`DownloadGB`	`project`
`EventCount`	`project`
`IsUnmanagedDevice`	`project`
`RiskIndicators`	`project`
`TimeGenerated`	`project`
`TotalDataGB`	`project`
`UniqueApplications`	`project`
`UniqueHosts`	`project`
`UploadGB`	`project`
`User`	`project`

`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)

Netskope - Anomalous User Behavior (High Volume from Unmanaged Device)

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Parameters

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `summarize`

Stage 5: `extend`

Stage 6: `where`

Stage 7: `extend`

Stage 8: `where`

Stage 9: `extend`

Stage 10: `project`

Indicators

Output fields

Keyboard shortcuts

Search operators

Netskope - Anomalous User Behavior (High Volume from Unmanaged Device)

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Parameters

Stage 1: source

Stage 2: where

Stage 3: where

Stage 4: summarize

Stage 5: extend

Stage 6: where

Stage 7: extend

Stage 8: where

Stage 9: extend

Stage 10: project

Indicators

Output fields

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `summarize`

Stage 5: `extend`

Stage 6: `where`

Stage 7: `extend`

Stage 8: `where`

Stage 9: `extend`

Stage 10: `project`