Malicious PowerShell StreamReader WebRequest Download Cradle

ATT&CK techniques

Execution → C2

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects PowerShell constructing an IO.StreamReader over a Net.WebRequest response stream and executing it, the fileless NetSupport RAT ClickFix cradle. The loader used this in-memory download-and-execute technique to pull its next stage without writing a script to disk. Reflective download cradles built from StreamReader and WebRequest are almost exclusively malicious.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

Suspicious PowerShell Download Cradle via Net.WebClient DownloadFile

Malicious ClickFix Clipboard Command Execution via PowerShell

Suspicious PIKABOT PowerShell Download to Public Directory via Process Creation

Suspicious PowerShell Script Fetching Remote Batch File From Paste Site (via ps_script)

Suspicious PowerShell Download of Payload From Pastebin (via process_creation)

Suspicious PowerShell Remote Download and Execution via Invoke-WebRequest

Suspicious PowerShell Download Cradle via ClickFix Fake CAPTCHA (via process_creation)

Suspicious PowerShell Download of lib.zip Archive

Malicious ActiveMQ Exploitation Java Spawning PowerShell Downloader (via process_creation)

Malicious PowerShell StreamReader WebRequest Download Cradle

Pivot detection · T1059.001 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

Full detection rule

Unlock this rule to view and copy it

The detection logic is included with a plan. Everything else — context, mappings and implementation details — stays free on this page.

Sign in for 3 free unlocks

Signing in gives you 3 unlocks to spend on any rule in the library. No card, and they do not expire.

Also included

Unlocked rules convert on this page — to Splunk SPL or Splunk — Raw Index SPL or Microsoft Sentinel KQL or Microsoft Sentinel ASIM ASIM KQL or Microsoft Defender XDR KQL or Elastic Security KQL or Elastic Security Lucene or Elastic Security ES|QL or CrowdStrike Falcon CQL or SentinelOne PowerQuery or Palo Alto Cortex XDR XQL or Carbon Black Cloud Platform Search or Carbon Black EDR Process Search or Google Security Operations UDM Search or IBM QRadar AQL or Sumo Logic Cloud SIEM Rules expression or Rapid7 InsightIDR LEQL or Graylog Search or OpenSearch Lucene or OpenSearch PPL PPL or Grafana Loki LogQL or SQLite SQL or Zircolite SQLite — with the log-source profile the engine picked, the field map it used, and everything it could not express. Converting a rule you have unlocked costs no further credit.

See it run on a free rule →Convert your own rule →