Sigma rule: Suspicious Download and Execute Pattern via Curl/Wget

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-b7d93d787616, updated 2025-06-17T00:00:00.000Z.

Rule

Title
Suspicious Download and Execute Pattern via Curl/Wget
Status
experimental
Level
high
Author
Aayush Gupta
Date
2025-06-17
File
rules/linux/process_creation/proc_creation_lnx_curl_wget_exec_tmp.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects suspicious use of command-line tools such as curl or wget to download remote
content - particularly scripts - into temporary directories (e.g., /dev/shm, /tmp), followed by
immediate execution, indicating potential malicious activity. This pattern is commonly used
by malicious scripts, stagers, or downloaders in fileless or multi-stage Linux attacks.

Log source

product
linux
category
process_creation

Detection

selection_downloader:
    CommandLine|contains:
        - '/curl'
        - '/wget'
selection_tmp:
    CommandLine|contains:
        - '/tmp/'
        - '/dev/shm/'
selection_executor:
    CommandLine|contains: 'sh -c'
condition: all of selection_*

False positives (as the rule lists them)

  • System update scripts using temporary files
  • Installer scripts or automated provisioning tools

Tags

  • attack.execution
  • attack.t1059.004
  • attack.t1203

MITRE ATT&CK ids this rule names

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/linux/process_creation/proc_creation_lnx_curl_wget_exec_tmp.yml

Sources and licences

  • SigmaHQ

    "Suspicious Download and Execute Pattern via Curl/Wget" by Aayush Gupta (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/linux/process_creation/proc_creation_lnx_curl_wget_exec_tmp.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Suspicious Download and Execute Pattern via Curl/Wget",
entity page, dataset version ref-b7d93d787616, updated 2025-06-17T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/a2d9e2f3-0f43-4c7a-bcd9-9acfc0d723aa (accessed 2026-11-03).
Underlying source: SigmaHQ rule a2d9e2f3-0f43-4c7a-bcd9-9acfc0d723aa, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.