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Netskope - Excessive Downloads Detection (Spike vs Baseline)

Description

Detects users with excessive download activity compared to their 7-day baseline. Triggers when current download volume exceeds 3x the average.
Rule type
Scheduled
Version
1.0.0
Declared status
Available
Query frequency
1h
Query period
7d
Trigger
gt 0

Declared MITRE coverage

Declared sources

Metadata from the source file. No dependencies inferred from KQL.

Connectors

Data types

KQL query

Original query, unchanged.

let lookbackPeriod = 7d;
let currentPeriod = 1h;
let threshold = 3;
let baseline = NetskopeWebTransactions_CL
    | where TimeGenerated between (ago(lookbackPeriod) .. ago(currentPeriod))
    | where isnotempty(CsUsername)
    | where XCsAppActivity =~ 'Download' or ScBytes > 0
    | summarize 
        BaselineAvgBytes = avg(ScBytes),
        BaselineTotalBytes = sum(ScBytes),
        BaselineCount = count()
        by CsUsername
    | extend BaselineDailyAvg = BaselineTotalBytes / 7;
let current = NetskopeWebTransactions_CL
    | where TimeGenerated > ago(currentPeriod)
    | where isnotempty(CsUsername)
    | where XCsAppActivity =~ 'Download' or ScBytes > 0
    | summarize 
        CurrentTotalBytes = sum(ScBytes),
        CurrentCount = count(),
        Apps = make_set(XCsApp),
        Files = make_set(XCsAppObjectName)
        by CsUsername;
current
| join kind=inner baseline on CsUsername
| where CurrentTotalBytes > (BaselineDailyAvg * threshold)
| extend 
    SpikeMultiplier = round(CurrentTotalBytes / BaselineDailyAvg, 2),
    CurrentTotalMB = round(CurrentTotalBytes / 1048576.0, 2),
    BaselineDailyMB = round(BaselineDailyAvg / 1048576.0, 2)
| project 
    TimeGenerated = now(),
    User = CsUsername,
    CurrentDownloadMB = CurrentTotalMB,
    BaselineDailyAvgMB = BaselineDailyMB,
    SpikeMultiplier,
    DownloadCount = CurrentCount,
    ApplicationsUsed = Apps,
    FilesDownloaded = Files

Declared entities

Account

Related content

Links established from declared identifiers and solution manifests.

Source provenance

GitHub

Displayed values come from files in Azure/Azure-Sentinel. They describe the published template, not your workspace configuration.

Source identifier
dd0ebd84-ffbe-45df-848b-0615ac446b04
Additional source files 2Solutions/NetskopeWebTx/Analytic Rules/NetskopeWebtx_Rule3.yamlsource ↗Solutions/NetskopeWebTx/Data/Solution_NetskopeWebTx.jsonsolution-membership ↗
GSTEP / CATALOG TRACKING

Added to catalog : 16 Sept 2026 · 05:49 UTC
Last change observed : 16 Sept 2026 · 05:49 UTC

GSTEP sync dates, separate from the source content’s publication dates.