huntrule

Suspicious Curl POST Downloading PowerShell Payload to Temp Directory (via process_creation)

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-07-03
Updated
2026-08-28
AnalysisDetection

ATT&CK techniques

C2

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule detects curl issuing an HTTP POST request whose output is a PowerShell script, the ingress technique used in the Axios NPM supply chain attack where cmd.exe piped a curl POST response into a .ps1 file in the Temp directory. Adversaries stage second-stage scripts this way to pull payloads from attacker infrastructure, so the combination of curl, a POST verb, and a PowerShell target file is worth alerting on.

Reporting behind it

Related detections9 linkedT1105 — drag to rearrange
Malicious Hidden Virtual Machine Launched via QEMU for Persistence
Suspicious node.exe Execution Spawned by PowerShell
Suspicious Executable Download to Temp Directory via curl on Linux
Suspicious BITSAdmin File Transfer Into ProgramData via Process Creation (via process_creation)
Suspicious PowerShell Download Cradle via IEX and DownloadString (via process_creation)
Suspicious Remote File Download via certutil URLCache (via process_creation)
Suspicious WebDAV Retrieval via rundll32 and davclnt.dll (via process_creation)
Suspicious PowerShell Download to Temp and In-Memory Execution via IEX (via process_creation)
Suspicious PowerShell Download of Bumblebee Stager Files (via process_creation)
Suspicious Curl POST Downloading PowerShell Payload to Temp Directory (via process_creation)
Pivot detection · T1105 · 9 related

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