HH.EXE Execution

Severity: low
Author: E.M. Anhaus (originally from Atomic Blue Detections, Dan Beavin), oscd.community
Source: upstream

Detects the execution of "hh.exe" to open ".chm" files.

MITRE ATT&CK coverage

Tactic	Techniques
Defense Evasion	`T1218.001` System Binary Proxy Execution: Compiled HTML File

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `all of selection_img`

or:
Image|endswith: '\hh.exe'
OriginalFileName: HH.exe

Stage 2: `all of selection_cli`

CommandLine|contains: .chm

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	`.chm` corpus 2 (sigma 2)
`Image`	ends_with	`\hh.exe` corpus 14 (sigma 14)
`OriginalFileName`	eq	`HH.exe` corpus 5 (sigma 5)