Linux Process Sets HTTP/HTTPS Proxy Environment Variables

Flags Linux process command lines that set http_proxy and https_proxy values, indicating proxy configuration.

FreeReviewedSigma · Low · v2

Product: linux
Category: process_creation
Author: Ömer Günal (SigmaHQ), DRL 1.1
Published: 2020-06-17
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
- T1090Proxy
Exfiltration
Impact

What it detects

This rule flags Linux process creations where the command line includes proxy environment variable assignments for both http_proxy= and https_proxy=. Attackers may use proxy settings to route outbound traffic through intermediate systems for command-and-control or to evade direct network visibility. Detection relies on process creation telemetry and specifically inspects the process command line for these substrings.

Reporting behind it

github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/linux/process_creation/proc_creation_lnx_proxy_connection.yml

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Malicious GenAI Browser Extension C2 and PAC Redirection (via proxy)

Malicious FRP Reverse Proxy Tunnel Identified by Hardcoded Token (via process_creation)

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Suspicious Chisel SOCKS Tunnel Command Line

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Linux Process Sets HTTP/HTTPS Proxy Environment Variables

Pivot detection · T1090 · 9 related

Changelog

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-process-sets-http-proxy-https-proxy-environment-variables-72f4ab3f

title: Linux Process Sets HTTP/HTTPS Proxy Environment Variables
id: 0d14b7ab-99f5-412c-ab52-f6bbfc41ff1e
status: test
description: This rule flags Linux process creations where the command line includes proxy environment variable assignments for both http_proxy= and https_proxy=. Attackers may use proxy settings to route outbound traffic through intermediate systems for command-and-control or to evade direct network visibility. Detection relies on process creation telemetry and specifically inspects the process command line for these substrings.
author: Ömer Günal, Huntrule Team
date: 2020-06-17
modified: 2022-10-05
tags:
  - attack.command-and-control
  - attack.t1090
logsource:
  product: linux
  category: process_creation
detection:
  selection:
    CommandLine|contains:
      - http_proxy=
      - https_proxy=
  condition: selection
falsepositives:
  - Legitimate administration activities
level: low
license: DRL-1.1
related:
  - id: 72f4ab3f-787d-495d-a55d-68c2ff46cf4c
    type: derived
references:
  - https://github.com/SigmaHQ/sigma/blob/master/rules/linux/process_creation/proc_creation_lnx_proxy_connection.yml

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