↳ GitHub sourceAnalytics ruleMedium

Base64 encoded Windows process command-lines (Normalized Process Events)

Description

'Identifies instances of a base64 encoded PE file header seen in the process command line parameter. To use this analytics rule, make sure you have deployed the [ASIM normalization parsers](https://aka.ms/ASimProcessEvent)'
Rule type
Scheduled
Version
1.1.4
Query frequency
1d
Query period
1d
Trigger
gt 0

Declared MITRE coverage

KQL query

Original query, unchanged.

imProcessCreate
| where CommandLine contains "TVqQAAMAAAAEAAA"
| where isnotempty(Process)
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), count() by Dvc, ActorUsername, Process, CommandLine, ActingProcessName, EventVendor, EventProduct
| extend AccountName = tostring(split(ActorUsername, @'\')[1]), AccountNTDomain = tostring(split(ActorUsername, @'\')[0])
| extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)
| project-away DomainIndex

Declared entities

AccountHost

Source provenance

GitHub

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

Source identifier
f8b3c49c-4087-499b-920f-0dcfaff0cbca
Additional source files 1Detections/ASimProcess/imProcess_base64_encoded_pefile.yamlsource ↗
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.