Windows: Flag 3CXDesktopApp updater fetching a known compromised update URL

Alerts on 3CXDesktopApp updater.exe launched with update arguments pointing to a known compromised HTTP update path.

FreeReviewedSigma · High · v3

Product: windows
Category: process_creation
Author: Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published: 2023-03-29
Updated: 2026-07-31

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1218System Binary Proxy Execution
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule identifies the 3CXDesktopApp updater process (update.exe) launching with update parameters that include an HTTP download URL targeting a specific Electron update path. Such behavior is important because malicious software distribution or supply-chain tampering can use legitimate updaters to deliver attacker-controlled binaries. The detection relies on Windows process creation telemetry, matching the updater executable path and required command-line substrings.

Reporting behind it

Related detections9 linkedT1218 — drag to rearrange

Suspicious Cabinet Extraction of Masqueraded vstm Archive via extrac32

Malicious DLL Execution via Wuauclt Update Handler (via process_creation)

Malicious aspnet_compiler.exe Injection Host Spawned by PowerShell via process_creation

Malicious regsvcs LOLBin Loading Ransomware DLL from UNC Path

Suspicious RegAsm or RegSvcs Spawned by Script Host (via process_creation)

Suspicious Extexport DLL Side-Loading Execution

Malicious ClickFix Execution Chain Spawning MSHTA via Pcalua on EtherRAT Infection

Suspicious TALONITE Certutil LOLBIN Decode and Download Abuse (via process_creation)

Suspicious Renamed git Binary gcmd.exe Execution (via process_creation)

Windows: Flag 3CXDesktopApp updater fetching a known compromised update URL

Pivot detection · T1218 · 9 related

Changelog

v3
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-process-creation-3cxdesktopapp-updater-fetching-known-compromised-update-e7581747

title: "Windows: Flag 3CXDesktopApp updater fetching a known compromised update URL"
id: 276d3b9c-637d-4e31-8067-70944f8fb6d9
related:
  - id: 3c4b3bbf-36b4-470c-b6cf-f07e8b1c7e26
    type: similar
  - id: 76bc1601-9546-4b75-9419-06e0e8d10651
    type: similar
  - id: bd03a0dc-5d93-49eb-b2e8-2dfd268600f8
    type: similar
  - id: 51eecf75-d069-43c7-9ea2-63f75499edd4
    type: similar
  - id: 93bbde78-dc86-4e73-9ffc-ff8a384ca89c
    type: similar
  - id: 63f3605b-979f-48c2-b7cc-7f90523fed88
    type: similar
  - id: d0b65ad3-e945-435e-a7a9-438e62dd48e9
    type: similar
  - id: e7581747-1e44-4d4b-85a6-0db0b4a00f2a
    type: derived
status: test
description: This rule identifies the 3CXDesktopApp updater process (update.exe) launching with update parameters that include an HTTP download URL targeting a specific Electron update path. Such behavior is important because malicious software distribution or supply-chain tampering can use legitimate updaters to deliver attacker-controlled binaries. The detection relies on Windows process creation telemetry, matching the updater executable path and required command-line substrings.
references:
  - https://www.linkedin.com/feed/update/urn:li:activity:7047435754834198529/
  - https://www.huntress.com/blog/3cx-voip-software-compromise-supply-chain-threats
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/TA/3CX-Supply-Chain/proc_creation_win_malware_3cx_compromise_susp_update.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-03-29
tags:
  - attack.stealth
  - attack.t1218
  - attack.execution
  - detection.emerging-threats
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith: \3CXDesktopApp\app\update.exe
    CommandLine|contains|all:
      - --update
      - http
      - /electron/update/win32/18.12
  condition: selection
falsepositives:
  - Unknown
level: high
license: DRL-1.1

Convert

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

SplunkSPL