Suspicious Remote Script Download and Execution via iwr Piped to iex

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 using Invoke-WebRequest piped into Invoke-Expression to download and run an install script in memory, observed in a Huntress Komari intrusion that fetched install.ps1 to deploy the agent. The iwr into iex pattern executes remote code without writing the script to disk. This download-cradle technique is a common precursor to agent and tooling deployment.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

Suspicious node.exe Execution Spawned by PowerShell

Suspicious PowerShell Download Cradle via IEX and DownloadString (via process_creation)

Suspicious PowerShell Download to Temp and In-Memory Execution via IEX (via process_creation)

Suspicious ClickFix cv.bat Staging in Temp via PowerShell (via process_creation)

Malicious Silver Fox PowerShell Download Cradle via irm and iex (via process_creation)

Malicious DAEMON Tools Supply Chain Payload Download via PowerShell WebClient (via process_creation)

Suspicious PowerShell Remote File Download Cmdlets (via ps_script)

Suspicious PowerShell Download Cradle Writing Executable To Windows Temp

Suspicious File Download via PowerShell WebClient DownloadFile

Suspicious Remote Script Download and Execution via iwr Piped to iex

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 →