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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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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