Suspicious Persistence Via VMwareToolBoxCmd.EXE VM State Change Script

Severity: high
Author: Nasreddine Bencherchali (Nextron Systems)
Source: upstream

Detects execution of the "VMwareToolBoxCmd.exe" with the "script" and "set" flag to setup a specific script that's located in a potentially suspicious location to run for a specific VM state

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1059` Command and Scripting Interpreter

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `all of selection_bin_img`

or:
Image|endswith: '\VMwareToolBoxCmd.exe'
OriginalFileName: toolbox-cmd.exe

Stage 2: `all of selection_bin_cli`

CommandLine|contains: ' script '
CommandLine|contains: ' set '

Stage 3: `all of selection_susp_paths`

or:
CommandLine|contains: ':\PerfLogs\'
CommandLine|contains: ':\Temp\'
CommandLine|contains: ':\Windows\System32\Tasks\'
CommandLine|contains: ':\Windows\Tasks\'
CommandLine|contains: ':\Windows\Temp\'
CommandLine|contains: '\AppData\Local\Temp'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`CommandLine`	match	`script` corpus 2 (sigma 2) `set` corpus 4 (sigma 4) `:\PerfLogs\` corpus 6 (sigma 6) `:\Temp\` corpus 14 (sigma 14) `:\Windows\System32\Tasks\` corpus 3 (sigma 3) `:\Windows\Tasks\` corpus 6 (sigma 6) `:\Windows\Temp\` corpus 15 (sigma 15) `\AppData\Local\Temp` corpus 8 (sigma 8)
`Image`	ends_with	`\VMwareToolBoxCmd.exe` corpus 2 (sigma 2)
`OriginalFileName`	eq	`toolbox-cmd.exe` corpus 2 (sigma 2)