Detectionhighexperimental

Devcon Execution Disabling VMware VMCI Device

Detects execution of devcon.exe with commands that disable the VMware Virtual Machine Communication Interface (VMCI) device. This can be legitimate during VMware Tools troubleshooting or driver conflicts, but may also indicate malware attempting to hijack communication with the hardware via the VMCI device. This has been used to facilitate VMware ESXi vulnerability exploits to escape VMs and execute code on the ESXi host.

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Launch
Matt Anderson, Dray Agha, Anna Pham (Huntress)Created Fri Jan 0285f520e7-6f5e-43ca-874c-222e5bf9c0dewindows
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: '\devcon.exe'
        - OriginalFileName: 'DevCon.exe'
    selection_action:
        CommandLine|contains: ' disable '
    selection_vmci_pci:
        CommandLine|contains:
            - '15AD&DEV_0740' # VMware VMCI PCI device (Vendor 0x15AD = VMware, Device 0x0740 = VMCI)
            - 'VMWVMCIHOSTDEV' # VMware VMCI root host device driver name
    condition: all of selection_*
False Positives

Legitimate VMware administration, Tools installation/uninstallation, or troubleshooting driver conflicts.

Automated scripts in virtualized environments for device cleanup.

Testing & Validation

Regression Tests

by Swachchhanda Shrawan Poudel (Nextron Systems)
Positive Detection Test1 matchevtx

Microsoft-Windows-Sysmon

Rule Metadata
Rule ID
85f520e7-6f5e-43ca-874c-222e5bf9c0de
Status
experimental
Level
high
Type
Detection
Created
Fri Jan 02
Path
rules/windows/process_creation/proc_creation_win_devcon_disable_vmci_driver.yml
Raw Tags
attack.defense-evasionattack.persistenceattack.privilege-escalationattack.t1543.003attack.t1562.001
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