Detection rules › Sigma
Potential Suspicious Browser Launch From Document Reader Process
Detects when a browser process or browser tab is launched from an application that handles document files such as Adobe, Microsoft Office, etc. And connects to a web application over http(s), this could indicate a possible phishing attempt.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | T1204.002 User Execution: Malicious File |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
title: Potential Suspicious Browser Launch From Document Reader Process
id: 1193d960-2369-499f-a158-7b50a31df682
status: test
description: |
Detects when a browser process or browser tab is launched from an application that handles document files such as Adobe, Microsoft Office, etc. And connects to a web application over http(s), this could indicate a possible phishing attempt.
references:
- https://app.any.run/tasks/69c5abaa-92ad-45ba-8c53-c11e23e05d04/ # PDF Document
- https://app.any.run/tasks/64043a79-165f-4052-bcba-e6e49f847ec1/ # Office Document
author: Joseph Kamau
date: 2024-05-27
modified: 2025-10-07
tags:
- attack.execution
- attack.t1204.002
logsource:
product: windows
category: process_creation
detection:
selection:
ParentImage|contains:
- 'Acrobat Reader'
- 'Microsoft Office'
- 'PDF Reader'
Image|endswith:
- '\brave.exe'
- '\chrome.exe'
- '\firefox.exe'
- '\msedge.exe'
- '\opera.exe'
- '\maxthon.exe'
- '\seamonkey.exe'
- '\vivaldi.exe'
CommandLine|contains: 'http'
filter_main_microsoft_help:
CommandLine|contains: 'https://go.microsoft.com/fwlink/'
filter_optional_foxit:
CommandLine|contains:
- 'http://ad.foxitsoftware.com/adlog.php?'
- 'https://globe-map.foxitservice.com/go.php?do=redirect'
condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
- Unlikely in most cases, further investigation should be done in the commandline of the browser process to determine the context of the URL accessed.
level: medium
Stages and Predicates
Stage 0: condition
selection and not 1 of filter_main_* and not 1 of filter_optional_*Stage 1: selection
selection:
ParentImage|contains:
- 'Acrobat Reader'
- 'Microsoft Office'
- 'PDF Reader'
Image|endswith:
- '\brave.exe'
- '\chrome.exe'
- '\firefox.exe'
- '\msedge.exe'
- '\opera.exe'
- '\maxthon.exe'
- '\seamonkey.exe'
- '\vivaldi.exe'
CommandLine|contains: 'http'
Stage 2: not filter_main_microsoft_help
filter_main_microsoft_help:
CommandLine|contains: 'https://go.microsoft.com/fwlink/'
Stage 3: not filter_optional_foxit
filter_optional_foxit:
CommandLine|contains:
- 'http://ad.foxitsoftware.com/adlog.php?'
- 'https://globe-map.foxitservice.com/go.php?do=redirect'
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
CommandLine | match | https://go.microsoft.com/fwlink/ |
CommandLine | match | http://ad.foxitsoftware.com/adlog.php? |
CommandLine | match | https://globe-map.foxitservice.com/go.php?do=redirect |
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 |
|
Image | ends_with |
|
ParentImage | match |
|