Execution via stordiag.exe

Severity: high
Author: Austin Songer (@austinsonger)
Source: upstream

Detects the use of stordiag.exe to execute schtasks.exe systeminfo.exe and fltmc.exe

MITRE ATT&CK coverage

Tactic	Techniques
Defense Evasion	`T1218` System Binary Proxy Execution

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation
Security-Auditing	4688	A new process has been created.

Stages and Predicates

Stage 1: `selection`

or:
Image|endswith: '\fltmc.exe'
Image|endswith: '\schtasks.exe'
Image|endswith: '\systeminfo.exe'
ParentImage|endswith: '\stordiag.exe'

Stage 2: `not filter`

or:
ParentImage|startswith: 'c:\windows\system32\'
ParentImage|startswith: 'c:\windows\syswow64\'

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
`Image`	ends_with	`\fltmc.exe` `\schtasks.exe` corpus 45 (sigma 45) `\systeminfo.exe` corpus 9 (sigma 9)
`ParentImage`	ends_with	`\stordiag.exe`
`ParentImage`	starts_with	`c:\windows\system32\` `c:\windows\syswow64\`