Process Creation: curl on Linux

Flags Linux process starts for the curl binary, indicating potential remote file download or web requests.

FreeReviewedSigma · Low · v3

Product: linux
Category: process_creation
Author: Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published: 2022-09-15
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

Flags process creation events where the executed binary path ends with /curl on Linux. Attackers commonly use curl to retrieve remote content for payload staging or to perform basic web requests. The rule relies on Linux process creation telemetry that captures the executable image path.

Reporting behind it

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Suspicious HijackLoader PNG Payload Retrieval via ClearFake

Malicious Download Piped to Shell via curl or wget (via process_creation)

Process Creation: curl on Linux

Pivot detection · T1105 · 9 related

Changelog

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.

linux-curl-execution-observed-via-process-start-ea34fb97

title: "Process Creation: curl on Linux"
id: 7e6e4f5a-33d9-478c-b027-6f7c704e4c5b
status: test
description: Flags process creation events where the executed binary path ends with /curl on Linux. Attackers commonly use curl to retrieve remote content for payload staging or to perform basic web requests. The rule relies on Linux process creation telemetry that captures the executable image path.
references:
  - https://www.trendmicro.com/en_us/research/22/i/how-malicious-actors-abuse-native-linux-tools-in-their-attacks.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/linux/process_creation/proc_creation_lnx_curl_usage.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2022-09-15
tags:
  - attack.command-and-control
  - attack.t1105
logsource:
  category: process_creation
  product: linux
detection:
  selection:
    Image|endswith: /curl
  condition: selection
falsepositives:
  - Scripts created by developers and admins
  - Administrative activity
level: low
license: DRL-1.1
related:
  - id: ea34fb97-e2c4-4afb-810f-785e4459b194
    type: derived

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