Phishing Pattern ISO in Archive

Severity: high
Author: Florian Roth (Nextron Systems)
Source: upstream

Detects cases in which an ISO files is opend within an archiver like 7Zip or Winrar, which is a sign of phishing as threat actors put small ISO files in archives as email attachments to bypass certain filters and protective measures (mark of web)

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1566` Phishing

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: '\ImgBurn.exe'
Image|endswith: '\PowerISO.exe'
Image|endswith: '\isoburn.exe'
or:
ParentImage|endswith: '\7zFM.exe'
ParentImage|endswith: '\Winrar.exe'
ParentImage|endswith: '\peazip.exe'

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.