Windows curl.exe Process Creation

Alerts on execution of curl.exe on Windows, which may indicate remote downloads or web requests.

FreeReviewedSigma · Low · v5

Product: windows
Category: process_creation
Author: Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published: 2022-07-05
Updated: 2026-07-31

ATT&CK techniques

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

What it detects

This rule matches the creation of a process whose image ends with \curl.exe on Windows. Attackers may use curl to download files from remote locations or make HTTP/S requests as part of command-and-control or staging. Detection relies on Windows process creation telemetry that records the launched executable path and command execution events.

Reporting behind it

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Suspicious CloudZ RAT Payload Download via curl to ProgramData

Suspicious Velociraptor Agent Deployment via msiexec From Cloud Storage

Suspicious PowerShell Download of lib.zip Archive

Suspicious File Download Via Bitsadmin Transfer

Suspicious PowerShell Download Of Text-Disguised Payload

Explorer WebDAV UNC Download Using At-Port Syntax

Windows curl.exe Process Creation

Pivot detection · T1105 · 9 related

Changelog

v5
Candidate ingested via manual entry.2026-07-31
v4
Candidate ingested via manual entry.2026-07-31
v3
Candidate ingested via manual entry.2026-07-31
v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

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

windows-curl-exe-process-execution-for-remote-file-transfer-bbeaed61

title: Windows curl.exe Process Creation
id: fb3d7012-b801-4224-af08-380766334a10
related:
  - id: e218595b-bbe7-4ee5-8a96-f32a24ad3468
    type: derived
  - id: bbeaed61-1990-4773-bf57-b81dbad7db2d
    type: derived
status: test
description: This rule matches the creation of a process whose image ends with \curl.exe on Windows. Attackers may use curl to download files from remote locations or make HTTP/S requests as part of command-and-control or staging. Detection relies on Windows process creation telemetry that records the launched executable path and command execution events.
references:
  - https://web.archive.org/web/20200128160046/https://twitter.com/reegun21/status/1222093798009790464
  - https://github.com/SigmaHQ/sigma/blob/master/rules-threat-hunting/windows/process_creation/proc_creation_win_curl_execution.yml
author: Florian Roth (Nextron Systems), Huntrule Team
date: 2022-07-05
modified: 2023-02-21
tags:
  - attack.command-and-control
  - attack.t1105
  - detection.threat-hunting
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    - Image|endswith: \curl.exe
    - Product: The curl executable
  condition: selection
falsepositives:
  - Scripts created by developers and admins
  - Administrative activity
level: low
license: DRL-1.1

Convert

This rule as a query you can run. Uses no unlock credit.

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