DLL Execution via Rasautou.exe

Severity: medium
Author: Julia Fomina, oscd.community
Source: upstream

Detects using Rasautou.exe for loading arbitrary .DLL specified in -d option and executes the export specified in -p.

MITRE ATT&CK coverage

Tactic	Techniques
Defense Evasion	`T1218` System Binary Proxy Execution

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `all of selection_img`

or:
Image|endswith: '\rasautou.exe'
OriginalFileName: rasdlui.exe

Stage 2: `all of selection_cli`

CommandLine|contains: ' -d '
CommandLine|contains: ' -p '

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	`-d` corpus 6 (sigma 6) `-p` corpus 5 (sigma 5)
`Image`	ends_with	`\rasautou.exe`
`OriginalFileName`	eq	`rasdlui.exe`