Detectionhightest

Chromium Browser Headless Execution To Mockbin Like Site

Detects the execution of a Chromium based browser process with the "headless" flag and a URL pointing to the mockbin.org service (which can be used to exfiltrate data).

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Launch
X__Junior (Nextron Systems)Created Mon Sep 111c526788-0abe-4713-862f-b520da5e5316windows
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic
Detection Logic3 selectors
detection:
    selection_img:
        Image|endswith:
            - '\brave.exe'
            - '\chrome.exe'
            - '\msedge.exe'
            - '\opera.exe'
            - '\vivaldi.exe'
    selection_headless:
        CommandLine|contains: '--headless'
    selection_url:
        CommandLine|contains:
            - '://run.mocky'
            - '://mockbin'
    condition: all of selection_*
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

Testing & Validation

Regression Tests

by SigmaHQ Team
Positive Detection Testevtx

Microsoft-Windows-Sysmon

MITRE ATT&CK
Rule Metadata
Rule ID
1c526788-0abe-4713-862f-b520da5e5316
Status
test
Level
high
Type
Detection
Created
Mon Sep 11
Path
rules/windows/process_creation/proc_creation_win_browsers_chromium_mockbin_abuse.yml
Raw Tags
attack.execution
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