huntrule

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
AnalysisDetection

ATT&CK techniques

Defense Evasion

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. 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

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Windows: Flag 3CXDesktopApp updater fetching a known compromised update URL
Pivot detection · T1218 · 9 related

Changelog

v3
  1. v3
    Candidate ingested via manual entry.2026-07-31
  2. 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.