Suspicious Extrac32 Execution

Severity: medium
Author: frack113
Source: upstream

Download or Copy file with Extrac32

MITRE ATT&CK coverage

Tactic	Techniques
Command & Control	`T1105` Ingress Tool Transfer

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `all of selection_lolbas`

or:
CommandLine|contains: extrac32.exe
Image|endswith: '\extrac32.exe'
OriginalFileName: extrac32.exe

Stage 2: `all of selection_archive`

CommandLine|contains: .cab

Stage 3: `all of selection_options`

or:
CommandLine|contains: ' \\\\'
CommandLine|contains: '/C'
CommandLine|contains: '/Y'

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	`\\\\` corpus 8 (sigma 8) `.cab` corpus 5 (sigma 5) `/C` corpus 3 (sigma 3) `/Y` `extrac32.exe` corpus 2 (sigma 2)
`Image`	ends_with	`\extrac32.exe` corpus 2 (sigma 2)
`OriginalFileName`	eq	`extrac32.exe`