Suspicious Remote Child Process From Outlook

SIGMA detection rule by Markus Neis, Nasreddine Bencherchali (Nextron Systems) · NOASSERTION

Detects a suspicious child process spawning from Outlook where the image is located in a remote location (SMB/WebDav shares).

title: Suspicious Remote Child Process From Outlook
id: e212d415-0e93-435f-9e1a-f29005bb4723
related:
    - id: 208748f7-881d-47ac-a29c-07ea84bf691d # Outlook Child Processes
      type: similar
status: test
description: Detects a suspicious child process spawning from Outlook where the image is located in a remote location (SMB/WebDav shares).
references:
    - https://github.com/sensepost/ruler
    - https://www.fireeye.com/blog/threat-research/2018/12/overruled-containing-a-potentially-destructive-adversary.html
    - https://speakerdeck.com/heirhabarov/hunting-for-persistence-via-microsoft-exchange-server-or-outlook?slide=49
author: Markus Neis, Nasreddine Bencherchali (Nextron Systems)
date: 2018-12-27
modified: 2023-02-09
tags:
    - attack.execution
    - attack.stealth
    - attack.t1059
    - attack.t1202
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\outlook.exe'
        Image|startswith: '\\\\'
    condition: selection
falsepositives:
    - Unknown
level: high

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

257305e8-668b-4514-af05-f569a1ce65cc

Propose edits, view related rules, and engage with the community through comments.

Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

[[ reason ]]

What does this mean?

Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

[[ reason ]]

What do these messages mean?

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

Community Discussion